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Questions and answers until 21.08.1999

G.O.W. Kickback, part1:

Questions and Answers

Answered by: P. T. Kekkonen

Why all this teasing ?

In some countries are firearms silencers entirely free to buy and possess. In many other countries is possession of these devices banned or taxed heavily, saying nothing about this humiliating procedure of silencer/ buyer registration. Are you teasing millions of "gun nuts" especially in U.S. to violetions of the Federal Firearms Acts 1934 and 1968 by making this doubtful handloading information public ?

Anonyme American.


from PeTe:

That American "Lex Morgenthau" (F.F.A. in 1934) was a crime itself, because it was just a trick for collection of some extra tax-money for the financing of the New Deal of Franklin D. Roosevelt. Henry "Shylock" Morgenthau was a counsellor of F.D.R. in all of the financial matters, including taxation already before the presidency of F.D.R. Later he was rewarded by installment in the office of US Secretary of the Treasury. The New Deal was not a crime itself, but continuation of F.F.A. '34 was it, because there was no more need to collect extra taxation, when the Great Depression was over in the late 1930s.

I have mentioned many times that the skill to handload subsonic or transsonic rifle cartridges may be more useful to those shooters who are unable to acquire, possess or use the suppressor or silencer than to us lucky devils, who can buy a "sordino" more easity than a pack of cicarettes or bottle of low-proof beer. Every American gun-owner is, however, still under obligation to contact his Senator or other influential politician, and tell to him or her a message: "Revoke Lex Morgenthau and F.F.A. '68 !"

Photo: The silencer genius Hiram Percy Maxim. His "Maxim Silent Firearms" company introduced silencers to the American markets quickly and succesfully. Nevertheless, not everyone was yet ready to admire his inventions. The "Empire Strikeback" came in the form of taxation.


It is a funny trick to guide some supporter of silencer-ban to the shooting range, and shoot... not him or her, but... some shots with silencer / suppressor mounted with full-power cartridges, and then some shots without suppressor, using subsonic handloads, and then ask from the listener: "Which shots sounded to be less noisy ? Where is the common sense of Lex Morgenthau, which is so easy to evade by skilful handloading ??"

There was a partial ban of suppressors even in Finland since 1983 until 1993 by the Game Act: Use of the suppressor for game hunting was forbidden. That ban was, however, shown to be ridiculous by shooting trials like this, described above, and it was revoked silently by the general renovation of Finnish Game Legislature in 1st August 1993.

04081999; PeTe



Mosin-Nagant/AK/SKS with subsonics and replica silencer

Hi Pete,

Thanks for the excellent information on the Lapua B416 subsonic bullet, and the tip on enlarging the primer hole on cases to be used for subsonic loads only. I have two Soviet 3.5-power PU scopes, and will mount on a M -91/30 rifle and the other on a M1944 carbine. Willing to make a replica of the Soviet silencer used on the M -91/30.

Still some questions:

1) Do you have any drawing's on that silencer, and any loads that will stay subsonic in that rifle ?
2) Might I use the B416s ?
3) What is your impression of the Mosin-Nagant: How easy is it to make into a 7.62 x 39 weapon, like the one in "Silencer History and Performance", page 73.?

Chris.

  Hi, Chris ! Many thanks to you for reloading data and especially for E-mail address of ADI ! I presume, HODGDON's UNIVERSAL/ CLAYS powder is this same AP-30N, but I'll - of couse - ask it from that propellant company. There are two brands of powder, earning reputation "THE very best propellant for subsonic handloads": CLAYS and N 310, available everywhere in Civilized Free World. (And in Finland...)

Russian SOKOL and American BULLSEYE are also good for the purpose and applied to subsonic or trans-sonic rifle loads of calibers .30-06 and 7.62 Mosin-Nagant since The Beautiful Era / Le Belle Epoque i.e. an era before the First World War. Finnish researchers are able to get that SOKOL Poroh just sporadically and BULLSEYE is unavailable in Finland.

In the sub-arctic countries, like Finland, N 310 is slightly better than CLAYS, because it works more reliably in the frosty weather, but CLAYS is good for use in the summertime or indoor ranges. It is really clean-burning, according to those friends handloading revolver cartridges with CLAYS for the indoor use.


1) I have not a detailed drawings of Soviet GLUSHITYEL S-40 at hand. ("Detailed" = drawings with all dimensions of each & every part added in millimeters or inches & decimals). I have sometimes made a crude "exploded drawing" of S-40's parts and a sectionalized drawing, along with superficial illustration with some dimensions. This device is rather complicated with two rubber discs or wipes to shoot through. Bayonet mount of S-40 suppressor is clever and simple, thanks to "ancient" fixing method of Mosin-Nagant's spike bayonet.

Appearance of replica suppressor may be similar to that of S-40 "glushityel" (="suppressor" in Russian), and the jacket may be lengthened to ca. 170 mm (as it was in a rare S-43 version with three rubber wipes), but a simplified construction with baffles is recommended. Those may be straight plates of aluminium with a bullet passage hole, diameter 9 mm, and aluminium spacers between those baffles. Two or three rearmost baffles must be of steel. Recommended baffle thickness is 3 to 5 mm, and distances between baffles may be 7 to 10 mm, depending on cleanliness of powder burning: CLAYS powder charges may need mere 5 mm spaces between the baffles, due to the reduced percentage of solid residue.

This system is called as HUMBERT's Chamber Suppressor in one Finnish printed source, or GUMBERT Glushityel in Russian sources. Inventor was presumably a Russian Imperial Army officer (mentioned as Colonel in a Finnish scientific magazine, published in 1921). In the Western literature he is totally unknown designer, although design itself is applied for many suppressors, like that of STEN Mk IIS with a barrel unit Mk I. (See "SILENCER HISTORY AND PERFORMANCE" page 266). As a muzzle-can might Humbert suppressor be tried more than a hundred years ago.

"Telegraph operator" of GUNWRITERS shall dig some interesting drawings from our archives - like one showing a comparison between Humbert's and contemporary GREENER's baffle constructions. Neither Humbert nor Greener patented their inventions. So it is impossible to tell, who discovered a "silencer" and when - and where, in the case of Humbert. Imperial Russia is mentioned, because just Russian sources knows that designer today - and patenting was unknown practice there (?).

Example given: LEWIS WELLS BROADWELL, then a resident of Sankt Petersburg (presumably citizen of Russia), patented his famous metal sealing ring of breech-loading artillery pieces in England. His patent-attorney RICHARD A. BROOMAN was a "proforma inventor" in the British Patent Nr. 1281, signed with a seal of Queen VICTORIA in 13th Nov. 1863. There are just a handful of artillery experts in the Western World aware of Russian origin of that well-known invention, still up-to-date for designers bustling with caseless cartridges and gas-sealed revolvers.

Original Soviet-Russian loads with blackened brass cases were not subsonics. According to the "Tablicha" (= sight adjustment table, engraved on the jackets of S-40 suppressors) the muzzle velocity of 7.62 mm type 1908 Spitzer bullet (Lyohkaya Pulya) with weight 9.65 grams was ca. 470 meters per second. Cartridges for suppressed rifles were loaded also in Finland with about similar ballistics. Charge of them was 0.65 gram of VRT Blank Cartridge powder N 14. Shooting was as noisy with or without "glushityel", due to the flight noise of supersonic bullet, especially from long-barreled rifle m/1891.

According to French authority on 7.62 mm Mosin cartridges, PHILIPPE REGENSTREIF, there were subsonic factory-loaded Partizan cartridges with "L-bullet" and a charge 0.50 gram of quickly burning nitrocellulose powder issued already before German invasion to Soviet-Russia, but they were spent very soon, and the partizans were constrained to handload their noiseless cartridges in the "backwoods factories". (See article "ARCANE" for the further history). ½ gram of SOKOL or other similar powder seems to be an excessive charge behind a bullet with a weight 9.65 grams/ 149 grains, but those L-bullets were dimensioned to diameter 7.80 mm/.307", while the groove diameter of rifles may be 7.92 mm/ .312". A lot of powder gas was blown past the bullet, which got a nominal muzzle velocity mere 262 meters per second/ 860 f.p.s.


2) Bullet LAPUA B416 is designed for loading of subsonic cartridges to Russian-originated firearms with rifling twist 240 mm. It is suitable for Mosin model 1891 and 91/30 or carbine model 1944, along with 7.62 mm Kalashnikov variations. You may start handloading trials from the charge similar to that of German 7.9 mm Nahpatrone/Finower, with practically equal powder Vihtavuori N 320, from the charge 0.55 gram/ 8.5 grains. Carbine may develope higher muzzle velocities than a full-sized rifle. It is advisable to load cartridges for them exclusively. You may adjust the cartridge overall length so that the bullet almost touches the rifling. Lubrication of bullet's circumjacent grooves (cannelures) is usually beneficial. The powder charge needs no filling if you have enlargened the primer holes, or if your cases have pockets for BERDAN primers.

Minimum powder charge is 0.45 gram. Maximum load is ca. 0.90 gram, considering use of primer vent enlargement and use of a Magnum primer, or big Berdan primer. Most accurate loads are unfortunately supersonic; charge 0.65 to 0.80 gram of N 320. (Every rifle and carbine has exclusive "best accuracy" charge. An outsider can tell just those limits of an area for seeking after this pet load. Ten grains of shotgun powder N 320 may be good in some rifle, with 200-grainer bullet, but sometimes may 12 grains give still better accuracy..! These target loads are developed for use of 200 grains LAPUA bullet D-166, but B416 is almost similar to these good old machine gun projectiles, designed in 1935 - 36 for then-planned indirect shooting to distances as long as 3 to 4 kilometers.


3) Making of "DeLISLE Carbine"-pattern silenced rifle from a Mosin-Nagant is not overly difficult task. You may use full length 7.62 x 54 Rimmed Russian Mosin-Nagant gartridges with drilled primer pockets and Magnum primers. No need to buy a custom barrel with 7.62 x 39 mm Yelisarova & Syemina chamber, which may be somewhat expensive. Also, no need to design a special magazine, or use the carbine as a single-shot rifle.

Suitable barrel length is about 350 mm - if you can drill and ream gas bleed holes through barrel walls. If you have not necessary equipment (tungsten carbide drill-bit and reamer), you must cut the barrel to the length ca. 500 mm. Suppressor may be similar to Finnish BR-Tuote Ky Telescopic Reflex TX8. You may presumably order one from BR-Tuote Ky with a gas expansion chamber length made according to your specifications. You can find a drawing of TX8 from a book "S.H.A.P" on the page 44. Suppressor of silenced (or almost SILENT) carbine on the page 73 of "S.H.A.P." is just this same model, and the carbine was custom-built by BR-Tuote. (That firm was established for building of highly accurate bench-rest shooting rifles, as the abbreviation in it's name tells).

That shooter, MARKO RUOTSALAINEN, is a friend of mine. We are both residing in the same town, Joensuu. Marko was surprised and somewhat sceptical when I told him that it was unnecessary to modify his carbine for shooting of 7.62 x 39 mm Ye & S (Kalashnikov) M-43 cartridges, because that old rimmed 7.62 mm Mosin cartridge can be handloaded to become equally silent.

Once upon a time it was actually factory-loaded to shoot "silent without silencer" by SAKO Oy in 1936 with lead bullets, and later in Soviet-Russia with jacketed oversized 8.0 mm "Ohotnichye" bullets, since 1943 or '44. (According to PHILIPPE REGENSTREIF, the jacket material was brass, but it might be brass-plated iron. Germans electroplated their iron-jacketed bullets with brass, when they needed very uniform bore friction. Plating might also be zinc, coated with potassium bi-chromate. It turns the zinc to look like brass).

After some shooting trials with 7.62 mm Mosin handloads Marko agreed with my idea that a reduced case volume is less important factor of subsonic cartridge, than are suitable burning rate of the powder (as fast or "hot" as available), suitable bullet material (well-lubricated lead alloy) and some little tricks - like enlargened primer vents.

You have presumably receiver-mounts for your PU scopes ? It is possible to weld the scope mounting base on the suppressor jacket, if it is of mild steel. The least expensive sight is, of course, an open front sight mounted on the suppressor jacket, and use of erected rear sight of the rifle for it's original purpose. As you can see, it is not difficult to DESIGN a silenced carbine. BUILDING of it is another story! I don't know your skill of metal machining, and the selection of power tools you can use for this project. Please, let me know! It is difficult to make "diagnosis" and predict a "prognosis" without "anamnesis" at all.

You must consider carefully, whether or not you shall adopt the barrel with gas bleed holes through the bore walls. Today, when the lead-alloy bullets with diameter ca. .311 -.312" are hard to find from sporting goods stores, but jacketed bullets are plentily available, is a barrel with gas bleed beneficial. If this situation shall become corrected - or you start to cast your own lead-alloy projectiles - is the barrel withOUT bleed holes recommended. Those apertures may peel off the bullet lubricant and make the bullet base asymmetric. Needless to say: A bullet with even slightly asymmetric BASE is hopelessly inaccurate. (Bullet POINT may be mutilated badly without notable ill effect on accuracy. This fact was discovered by Dr. FRANKLIN MANN and barrelsmith HARRY M. POPE more than a century ago).

Lead-alloy projectiles needs also "homeopatic" doses of powder as a propellant charge to get uniform muzzle velocities, shot after shot. Finnish SAKO 7.62 mm Mosin low-pressure cartridges of the first 1936 vintage were loaded with 0.30 gram/ 4.6 grains of powder N 14 (today N 310) and a lead-alloy bullet SAKO 110A LYIJY. That charge was later doubled to 0.60 gram, because those bullets - made with dies of jacketed 7.65 mm Luger bullets - were too thin for Russian-made rifles. Bullet weight was 6.0 grams/ 93 grains and material of them was an eutectic antimony-lead alloy, with 10 % antimony percentage. (Eutectic alloy has lowest possible melting point). Enhanced chamber pressure compressed the bullet and expanded it's base large enough to fill the grooves of Russian rifling.

For the 200 grains cast lead-alloy bullet you may use charges 0.40 gram/ 6.2 grains of N 320. (Charge of CLAYS may be still further reduced, if necessary). The muzzle pressure from a barrel with 500 mm length is low and easy to suppress: No need to drill and ream the powder gas bleed apertures..! Extented barrel lengtht means extensive telescoping powder gas expansion chamber of the suppressor, more volume, less pressure and a good silencing effect. (The original DeLISLE Silent Carbine had a very large diameter and volume of it's silencer unit. It shot .45 A.C.P. cartridges with about the same powder charges as are recommended for subsonic 7.62 mm Mosin cartridges. DeLisle gun was somewhat overly complicated: Powder gas bleed apertures through the bore walls were unnecessary, because of inherently subsonic muzzle velocity of .45 A.C.P. cartridge). Overall length of silent carbine with 500 mm barrel is slightly more than that of Marko's 7.62 x 39 mm "rifle", but not yet excessive, like the length of Mosin -91/30 with S-40 muzzle-can.

Once more: Many thanks to you for the address of ADI..!

Joensuu, FI, 27071999: PeTe



Suomi model with bipods?

Terve! I viewed your article on the Suomi and must commend you on your work. It was very informative. I do large military displays here in Canada for the Finnish War Veterans living here (primarily) in Toronto. I have several of the Suomi's which I have had sent from Finland (fully de-activated). One Suomi I was able to purchace here in Canada has a low serial number 711 . It is unique in that it has a from bipod and side selector. It looks similar to one in Markku Palokangas book but there is no foregrip.

Is there any way of finding out where this model was supposed to go ? I suspect it may have been an export model. I have been in conversation with a Robie Kulokivi in Joensuu and he has sent some good information on the series but not on a sample like this. Look forward to hear from you and I will send some photos of the displays I do over here.

Thanks again and Best Regards

Tero from Canada

  I have also some experience on the war-historical displays. The first one lasted one full month 10th June to 10th July 1988 in the village of Kovero, Tuupovaara, ca. 50 kilometers from my home-town Joensuu. I was there personally as an introducer 23 days (shifts ca. 10 hours, including short pauses for lunch and drinking of coffee - and some sips of sahti = kilyukalya = home made beer. It was a very hot summer, just like this one in 1999). In the Kovero Exhibition I could teach a lot of forgotten facts to the visitors. Disintegration of Soviet Union was just starting, and "the mental occupation" of Finnish common people was weakening. Among the visitors were many veterans of 2nd and 3rd Finnish Independence Struggles (1939 - 44). Many times I was no more a teacher but a pupil, listening carefully stories which may be still too incredible or atrocious to become published by magazines or books. (In Finland is the censorship, however, no more directed to particular articles, but towards the persons writing them).

Since this month-long exhibition we have erected historical displays, lasting one or two days, in Kuhmo (50th Anniversary Exhibition of the Winter War) which was repeated in Joensuu some months later, display in Joensuu when Suojeluskunta and Lotta-Svard organizations were officially rehabilitated and 50th Anniversary Exhibition of conclusive defence struggles of Ilomantsi War Theatre in August-September 1944. (Finnish Army was no more retreating, but attacking there and then. It never lost 3rd Independence War, frankly speaking, but our cowardly old politicians lost the peace negotiations - still once again).

Our guest of honour in this exhibition was ex-president of Finland, Mr. MAUNO KOIVISTO; a veteran of 1944 struggles. His "EMMA" (Russian 7.62 mm DP-27) light machine gun was just some months earlier found from a hidden secret arms depot in Eno, close to Joensuu. Our would-be next presidend, Mrs. ELISABETH REHN (then a Finnish Minister of Defence) was our guest of honour in Suojeluskunta/Lotta Exhibition - not only "ex officio" but also as a veteran of Lotta-Svard Association. Young girls were also mobilized in Finland as Pikku-Lotta members of L-S Association. These exhibitions or displays were set up by Pohjois-Karjalan Asehistoriallinen Kilta / Weaponry Historical Guild of North-Carelia.

Many details of SUOMI KP/-31 story are recollections of those veterans: Never published before the invention of WWW (this very first and still the only censorship-free mass media in the World History). Finnish version of SUOMI KP story is about three times as long as the same article in English. Part 5. and the Appendix, subject: Barrel Unit S.S.-II are still unfinished, and we are searching illustration for them. (I must re-learn my draughtsmanship, lost by the lack of exercise since 1996, when I became "blacklisted" by the publishers of periodical magazines and books in Finland. Drawing style for illustration of printed media differs also from a style which looks good on the computer screen and prints on the paper).

Yours SUOMI SMG with GREENER-styled fire selector and bipod is made presumably in 1934 or '35. Tikkakoski Oy had a lot of surplus bipods because sales of so called "Persian models" was failed due to passing away of king FEISAL the First in 1933. The new king GHAZI the First cancelled order of SUOMI SMGs, or England objected to export of those guns to Persia. Britons had still military bases there, and British Petroleum Company was owner of most oil-wells in Persia (today known as Iran). King Ghazi was threatened to "throw every Englishman away from his kingdom when Persian armed forces get necessary armament.!"

England was a very important buyer of Finnish products, like butter and timber in 1930s, during the Great Depression, and "Timber Dumping" from Red Russia. (A plot, which is still "taboo" in Finland, as well as striking in Finnish export harbors in the late 1920s. These political strikes "on the principle" were managed from the Red Russia.

Patriotic Finns responded by organizing Associate Vientirauha or a "scab army" - really armed with handguns - which could break most of the strikes and assure the important foreign trade). It was essential to maintain friendly relations with England and keep up a good reputation as a reliable trade partner, earned by hard way. Bipods of Persian Model SUOMI SMGs were mounted on the guns with a foregrip (which were not independent special models but just variations of KP/-31) and some really unique one-of-a-kind prototypes, like yours nr. 711. Tikkakoski Oy made them without orders from would-be exporter countries, but just for the sake of comparison and abandoned them because they offered no advantages over usual KP/-31.

Those trigger mechanisms with side selector were made by TOOL Oy or other sub-contractors for KONEPISTOOLI Oy's KP/-26. They were surplus or left-overs. Tikkakoski Oy was not produced them for KP/-31. There were old-fashioned trigger mechanisms for the comparisons still left in 1942, when AIMO J. LAHTI designed his improved SMG KP/-42 prototypes. Some of them had trigger module of KP/-26; some others mechanism of KP/-31. Russians and Germans made, however, submachine guns, prototype assault rifles and even the 7.9 x 57 mm machine guns by sheet steel stamping. Era of the 1st generation submachine guns was over. Germans had designed 3rd generation SMG already in 1940, and Russian G. SHPAGIN 2nd generation gun in 1941.

Finns could capture some Russian PPS 43 (SUDAYEV) guns in 1943 as a pattern of next submachine gun design, jumping from the expensive 1st generation KP/-31 to 3rd generation gun KP/-44, originally designed by Russian lieutenant BESCHRUZKI-VYSOZHKI in surrounded Leningrad. When the actual inventor was "disappeared to the oblivion", continued one ALEXEI SUDAYEV development of the gun, and in Finland completed designers T. SALO and E. KEKKI of Tikkakoski Oy this gun to accept all then-current types of KP/-31 magazines and clips, including 70 rd. drums. There were an amazing assortment of SUOMI SMG variations without exclusive model designation, and some others mentioned on some printed sources, although no more than one or a couple of prototype guns are actually made.

I have unfortunately no books by M. Palokangas in my possession or easily available for reading here and now. (To me these three books are too expensive. I have no income..Last moment's correction: Getting ca. $ 50:00 from one manuscript to local newspaper... and no more savings either. These stories are written literally racing an unevitable death. Despairing situation may explain my grim humor). My printed sources of information shows some odd variations of KP/-31 like "SUOMI-BERG" and "VKT-SUOMI KP/-30", but not a "SAKO-SUOMI", which I have seen ca. 15 years ago, and held it on my hands. It was not a fake..! Not all the KP/-31:s one-of-a-kind prototypes are listed on the book-keeping of Tikkakoski Oy and SAKO Oy - I presume...

Just one example given: In 1939 visited one general GASTRO of Brazilian Army in Finland. He got THREE different variations of SUOMI KP/-31 as a souvenir from Finland for comparison in Brazil. They were not yet licensed copies MADSEN-SUOMI m/-41 or guns made or assembled and finished by Swiss HISPANO-SUIZA, models -43 or -43/44, offered for sale to Brazil and Portugal in mid-40s. All three wariations of KP/-31 were made in Finland, and it was year 1939..!

Summa summarum: There are still some versions of KP/-31 unknown to the authors of Finnish books on firearms history - and also unknown to independent researchers like me or Robie Kulokivi. Your SUOMI KP/-31 is not a "Brazilian model", since there were not such variation existing.! In 1939 were bipods abandoned, and the serial number as low as 711 denotes early date of manufacturing; presumably 1934, when all the visions of export to Persia were definitively forgotten.

You possess, however, an one-of-her-kind piece of equipment, a treasure, despite of it's de-activated condition. (De-activation is, on the other hand, a more serious crime than a homicide: There are 5½ billions of EXCESSIVE peoples on the Globe, but presumably just one SUOMI KP/-31 like your's specimen). When Finnish government sold surplus firearms to Canada, they were not assorted, but shipped over there "in bulk" and paid by weight. Rusty old Mosin-Nagant rifles, picked up from Fellman's Field after the surrender of Red Guard in 1918 - or the very most rare prototype firearms - were treated as badly.

Joensuu 26071999: PeTe





Reduced loads

Hi, First to say that the information provided on your site is just great and unmatched in the World Wide Web. I got a question related to your Cat's Sneeze .223 answer (great article more to say). You mention that 3 to 4 grains of fast burning powder (like N310 or Clays) could be used in a .223 cartridge. Also you mention in the same answer the danger of Reduced Charge Detonation (on RIFLE powder).

Questions: 1) Could not a R.C.D / S.E.E happen with only 3 grains of fast powder in a .223 cartridge which normally holds 20+ grains ?

2) Would you need to fill up the cartridge with "other stuff" to keep the powder concentrated on the case bottom ?

3) Have you ever made any experience using VECTAN BA10 pistol powder on sub-sonic loads ? Or VECTAN Tubal 2000 rifle powder, which the manufacturer specifically recommends for reduced loads ? (VECTAN's site is at: www.nobelsport.snpe.fr/fr/PAGES/35_36.htm )

Best regards; Peter

  1) "When Lady Luck kiss you goodbye, it is still goodbye!" As small charge of powder as .2 gram or 3.1 grains of shotgun powder is able to blow up action of  a .308 Winchester rifle. (My empirical knowledge is based on test-shootings with .308).

That charge is half from definitively minimum load with a jacketed bullet, weighing 123 grains/ 8 grams and about one third from a safe minimum charge for .308 Win. with 170 grains / 11 grams jacketed bullet. The very same .20 gram / 3.1 grains is good, safe and subsonic charge for .308 Win. with a cast, lubricated lead alloy bullet with nominal weight 93 grains. Powder used for test-shootings was Finnish VIHTAVUORI N 320 (a most close counterpart of German blank-cartridge powder, adopted in 1933 and used as a propellant of 7.9 x 57 mm Mauser subsonic "Nahpatronen", loaded by Finower Industrie GmbH during WW II).

Two known accidents were also happened with reduced charges of that same powder by S.E. Effect. One with halved Definitively Minimum Charge and another with third D.M.C. Charge was in both instances before mentioned .20 gram / 3.1 grains. Bullets were - of course - jacketed ones, weighing 123 grains and 170 grains.

According to my test-shooting records is one full gram / 15.4 grains of N 320 safe charge behind both of these bullets in .308 Winchester cartridge with a standard (non-Magnum) Large Rifle primer. Powders N 310 or CLAYS are as or more easy to ignite as N 320, and so fit for use in reduced charge loads. This is the very most important quality of a powder, when the subsonic muzzle velocity is aspired after. Fast burning-rate and clean burning of powder are also beneficial - if not essential - properties.

An overly-reduced charge is a good way to court disaster, but reduced charge detonations are never (?) happened with a first shot of a string, when the rifle bore is still clean and at least slightly moistened with oil or grease. Risk of S.E.E. is increasing when the bore is fouled with carbon, lead dust from primers and unburned powder kernels, when the oil or grease is shot away from the bore.

First signal of imminent danger is increased variation of bullet velocities. A bullet, lodged into the bore, scares me always to have nightmares in seven to fourteen next nights... Velocity variations are usually not progressive but undulating because of variable bullet friction in the bore. Especially that friction (hardness) of jacketed bullets tends to vary, when the powder pressure behind them is low. Unfortunately this pressure cannot be higher, if one is trying to get subsonic velocity with each & every shot from the rifle, giving usually Mach 3 readings of bullet speed - like .223 .

A main reason of S.E.E. is disorder of powder ignition. Powder charge does not burn after the explosion of a priming pellet. It smoulders like a German tinder, developing a cocktail of explosive gasses like nitrogen oxides, hydrogen (very reactive "In Statu Nascendi" hydrogen - not yet bound to H2 molecules), and carbon monoxide. When this highly flammable mixture of gasses catches fire from still smouldering solid powder remnants, may the "BANG !" be horrible. Mere three grains of gasses may literally wreck the strong .308 Win. rifle action. (Three grains of smouldered solid powder is still three grains of material, despite of it's gaseous form of existence).

Maximum allowed chamber pressure of .308 Win. factory-loaded cartridges is 3600 atmospheres. Case head stands 4000 atm. but the action may be hard to open and the empty shell is usually no more reloadable. Primer pocket may be enlarged and/or the primer blown. Pressure 4200 to 4500 atm. may blow the case head, and the action of many rifles stands as much pressure as the cartridge head; no more.

Severe hand and/or eye injuries of the shooter are possible if the action fails. Eye injuries, including the permanent loss of eyesight, are possible, when the case head fails. This depends on construction of firearm's action, but use of eye protection is always advisable when one is bustling with weaponry. Highest measured detonation pressure was 10 000 atmospheres. A pietzo-electric pressure gauge was broken and highest grade on the pressure scale was this 10 kilobars. A sturdy test-barrel of a German gun-proofing laboratory was wrecked, of course.

This disastrous test was repeated with another set of equipment for the sake of comparison. Pressures of first shots were slightly less than normal. It might be fifth or sixth shot, when the new test-shooting barrel blew up. Again a pressure gauge disintegrated and a scale told: 10 000 atmospheres! It was presumably just a fraction from whole horrible truth, because so called "wave pressure" of a detonation may exceed reading A HUNDRED THOUSAND ATMOSPHERES, when the explosive material is in gaseous form of existence, pre-heated and pressurized before explosion.

Caliber of tested cartridge was .243 Winchester, bullet weight 80 grains, powder then-new NORMA MRP, and the charge... surprisingly... just 15 % less than a maximum (compressed !) load. It was STILL A REDUCED CHARGE DETONATION; not one caused by an excessive charge, because the charge could not be excessive with those components in use. Light bullet and slowly burning powder is not an advisable combination of loading components for .243 Win., known as a caliber prone to S.E. Effect. (It's "big brother" .308 and "kid brother" .22-250 are considerably less risky; last mentioned presumably because of more steep 25 degrees shoulder angle).

Needless to say: All the loading components were examined carefully afterwards. They were faultless. Just the burning rate of powder was selected wrongly for the bullet weight. MRP powder is O.K. for .243 Win., but for the heaviest bullets of this caliber; weight 100 or 105 grains. For the most usual 90 grainer bullets is some more fast-burning propellant advisable.

Noted was a slightly less than a tenth of second lasting delay between hit of a striker and explosion. This same delay is noted also by survivors of S.E.E. accidents, if they can remember something from the "big bang". (Usual recollection is: "I squeezed the trigger and woke up in the hospital"). If the delay lasts a second or more, it is just an usual hang-fire, without signs of excessive pressure.

These experiences may tell something about nature of S.E.E. Fortunately enough, not all hangfires lead to detonation, but they are warning signals: Something is gone wrong - or going "Helvetin kuuseen..!" (= towards the disaster). Powder & bullet combination may be wrong, or the primers are faulty: Deteriorated by handling with greasy or oily fingers. Priming pellet may be crushed with excessive priming force..!

I have very limited experience on handloading of .223 cartridges, but some knowledge on powders and loading of .308 Win. cartridges. You wonder, how is possible to use charges as small as 3 grains in cartridges loaded usually with 20 + grains of powder ? Rifle powders and those ones suitable for subsonic loads are entirely different stuffs, despite of almost similar chemical composition. Rifle powders are coated to become hard to ignite unless the cartridge case is almost fulfilled. They are also dense material even when grained or divided to kernels. Example given: A scoop or dipper, with a volume one cubic centimeter, filled with HODGDON "BALL-C 2", holds an even gram of powder; i.e. weight-per-volume ratio is 15.4 grains or 1 gram per cubic centimeter.

This same dipper filled with factory-fresh N 310 holds 7.7 grains or .5 (or ½) gram of powder. Kernels of N 310 are like short stumps of fine monofil Nylon fishing line, while BALL-C 2 looks like slightly flattened lead shots (pellets of a shotgun shell). A microscope with magnification 100 x shows smooth surface of BL-C 2, while kernel of N 310 looks like a round log, eaten by woodborer beetles, or surface of a sponge. Kernels of N 310 are made porous with added saltpeter (potassium nitrate) in the gelatinized powder mass. This salt is washed away with hot water after extrusion and cutting of powder.

Some handgun/shotshell powders may be made porous by a process called "popcorning". BL-C 2 and HODGDON HP-38 are formed as small pellets from the droplets of gelatinized nitrocellulose, with use of so much added volatile solvent that the powder dough looks like syrup. Droplets are hardened in the warm or hot salt water or "brine". Volatile solvent shall evaporate away from spherical kernels slowly or more rapidly, depending on temperature of the brine.

BL-C 2 is hardened in a warm brine to make solid or dense kernels. Porous "ball powder" / spherical powder was discovered accidentally in early 1930's when the method of manufacturing was just invented. Sometimes the brine was over-heated. Volatile solvent evaporated away too suddenly. Instead of the cute, dense and smooth spheres became the kernels porous and ugly, because steam of the solvent was trapped into the hardened droplets. Those "popcorned" kernels were returned to gelatinizing vessel as a "spoilt batch", but somebody discovered that handgunners and shotgunners needs just this porous, easily igniting and fast-burning porous powder, since the production of good old Bulk Shotgun Powders was discontinued some years earlier, because of somewhat risky manufacturing methods of them.

Popcorned kernels were somewhat too rapidly burning, but it was easy to lessen porosity of them by rolling them to become flattened flakes, and so let the remnants of solvent to ooze out. Then are the kernels impregnated with nitroglycerol. BL-C kernels are coated with a chemical called Centralite, which shall retard the burning rate of powder just after the ignition and so render the progressive burning of powder kernels. Flattened kernels of HP-38 are ready for packing without more measures; so I presume..!

For the handloading of subsonic rifle cartridges may the popcorned UNrolled spherical powder be almost ideal propellant, just like Bulk Powders were in the turn of 20th century. Powder manufacturers, however, seems to hate idea of reduced charge handloading "in corpore"..! (This fact is noted by experience since early 1980's).

But now back to your question: Ratio between 3 grains and (say) 21 grains is 1 : 7. Let's look .308 Winchester handloads.! Safe minimum charge with powder N 320 and 123 grains / 8 grams bullet (LAPUA S 374) was .40 gram / 6.2 grains, with Large Rifle Standard primer. (Magnum primer and lubrication of bullet may lessen the velocity variation). Suggested maximum charge of BALL-C 2 powder for bullets with weight 125-130 grains is 51 grains. Ratio between reduced charge and BL-C 2's charge is 1 : 8.23 !

Let's compare loads with 100 grains bullets. A very accurate load with SPEER "PLINKER" bullet was .35 grams / 5.4 grains of N 320. HODGDON's Data Manual gives 50 grains of H380 as Maximum Load. Ratio is 1 : 9.25. (I presume, it is actually about 1 : 10, because fifty grains of H380 seems to be slightly reduced charge. Maximum Load for 150 grains bullets is 51 grains of H380). One to seven ratio is presumably safe in .223 too.

Once again I must nag that there is no Definitive Handloading Data..!! Each & every loader must develop a load for his/her rifle or handgun exclusively by test-shooting. Outsider / adviser is able to give just some suggested starting loads, thought to be safe one. "Stepping up" or "stepping down" is done by handloader, using common sense.

Handloading of subsonic cartridges is a difficult task, because there are usually not REALLY GOOD bullets available over the counter. (Fortunate he/she, who has a rifle like .358 Winchester or .35 Whelen, able to shoot revolver bullets, which are plentily available everywhere). Lead bullets are very good projectiles for subsonic loads. Jacket is always more or less problematic, because it is a source of velocity variations.

On the other side: Loading of subsonics is also easy. No need to observe signs of excessive pressure, while stepping the charge up. When the bullet's flight noise is audible, the powder charge is excessive. Possession of the suppressor/silencer is unnecessary. When the rifle says: "CRACK !" and no more: "BOOM !" it is giving too high muzzle velocity for intended purpose. Charge must be stepped down or reduced slightly before loading more cartridges for continuing use.

2) A successful combination of powder, primer and bullet renders the case filler unnecessary, but there are just fair powders and jacketed bullets generally available for subsonic .223 handloads. A fluffy Dacron-fiber filling may be beneficial on the charge. It makes the ignition more constant, but it is unable to eliminate the ill effects from varying friction of bullet jackets = Variable muzzle velocities.

Another way for getting the sure and constant ignition is a simple treatment of cartridge cases: Enlargement of primer pocket vents or flash holes. Suitable diameter for Small Rifle primer vent is 3 millimeters / .12". Flash hole enlargement removes burrs from inside of vents and the ignition flash or flame shall become more sudden and broad, reaching each and every kernel of the powder almost simultaneously.

Those "subsonic special" cases with enlarged flash holes may be marked with green lacquered case-head or extractor groove dyed green with a felt-tipped marker. I don't know, whether or not it is risky to load usual rifle powder loads into these shells. I have sometimes accidentally loaded full-powered .308 Winchester handloads into the cases with priming vent drilled up to diameter 4.5 mm. Nothing extraordinary happened..!

3) Sorry, we have not VECTAN powders available in Finland. Just Vihtavuori and Hodgdon powders, and some friends have brought Russian SOKOL general purpose powder from Tallinn, Estonia. Since the amendment of Finnish Firearms Law and Act, I have no more right to possess firearms, cartridges or reloading components (except cases and bullets) because I am not a hunter or competition shooter. (I have a congenital dislike for all kinds of "sports" or "athletics").

Actual test-shooting activities I stopped in mid-1980's, because they were no more profitable: Finnish printed media - magazines or books - was hesitant to publish loading data of subsonic or other special loads, so called "economy reloads" with reduced powder charges. In 1992 suppressor tests I was, however, a loader of test-cartridges, because nobody else was able to load them in Finland to the muzzle velocities 160 - 1200 meters per second for .308 Winchester rifle. Since 1996 has no magazine published my articles in Finland. It is not just a censorship; it is a kind of "black-listing"..!

That's why I am unable to give to you exact reloading data for .223 cartridges, but just the most important information: An answer to the question "From what charge of what powder I can start the development of my handloads, with a minimized risk of the nasty surprises ?"

P.S. That story about two broken .243 Win. test-barrels and purposeful courting of S.E.E. in Germany is told in the book "Handbuch für den Wiederlader" by K.D.MEYER, who was then a director of German DEVA Institute.

24071999 PeTe



Lapua B416 and solvents

Hi PeTe ! I just bought some Lapua .308 B416 13.0 gram (200 gr) Subsonic bullets. Questions:

1) Have you any experience with them ? They are BT FMJs looking like a lead cast bullet. In the middle they have cannelures looking like lube grooves. They have driving bands, I think,to help stabilizing of the bullet in marginal twists.

2) Also I have read that, instead of a filler for keeping the powder charge near the bottom of the case, you can use some solvent to carefully dissolve the top layer of powder, which keeps the charge glued down in the bottom of the case. If so, what solvent do they use ? Glue ? Hoppes No. 9 ? What ?

Yours: Chris from other side of The Globe.


  1) Jess, I (or we) have ! With a slow 1 : 12" rifling twist that experience was unpleasant: We almost lost all the electronics from a CHRONY chronograph (bullet velocity measuring device) in 1992, when measuring bullet velocities for the table: ".308 BULLET FLIGHT NOISE vs. VELOCITY", published on page 70 of the book: "SILENCER HISTORY AND PERFORMANCE Vol. I" by ALAN C. PAULSON, publisher: PALADIN PRESS, Boulder, Colorado, U.S.A. (ISBN 0-87364-909-5). See also photos on page  "Suppressor Project Snapshots".

Lapua bullet B416 is designed primarily for the use in 7.62 mm military or assault rifles like old 7.62 mm Mosin-Nagant or Kalashnikov/ Valmet, with rifling twist 240 mm or 1 : 9.45". Users of these rifles report the bullets to be very accurate.

Our benchrest .308 rifle had a 1 : 12" rifling twist. Bullets were entirely unstable. One of them hit side-on just towards the CHRONY display screen, which was - fortunately enough - protected with a 1" thick plate of Acryl plastic. Dispersion of other hits was more than one square-meter at ca. 50 meters. Some bullets hit base-on, and most of them side-on to the target and we could get no velocity readings at 23 meters. Lady Luck was with us: The suppressor survived - intact.

"Relata refero" is 1 : 10" rifling marginally steep enough for stabilizing of B416 bullet in warm weather, but sometimes no more in a chilling frost. No friend of mine has experience with 1 : 11" twist. PLEASE: Do not use a suppressor/silencer on your rifle, when testing handloads with these bullets ! Suitable charge for .308 Winchester cartridge is 0.55 gram of VV N 320 or ca. ½ gram of CLAYS/UNIVERSAL powder. Equals old German 7.9 mm Mauser Nahpatrone. (Do you know E-mail address to Australian manufacturer of Hodgdon CLAYS ? I need some loading data for subsonic 9 mm Luger handloads with 147 grains bullet for submachine guns).

If you purchased them for your Sako TRG21, you must presumably sell those B416's to some friend having more steeply rifled gun, like a .30-06 or a 7.62 mm Mosin-Nagant. Especially good are these bullets for 7.62 x 39 mm Kalashnikov Avtomats or Valmets. It is possible to get subsonic velocity, along with functioning of autoloading. After some test-shots you'll presumably understand my friendly warning: In general, the bullet weight less than eleven grams is advisable for .308 Winchester subsonic loads !

Circumjacend grooves of B416 are designed for lessening of the bore friction. They have not stabilizing effect. Filling of these cannelures with a bullet lubricant like LEE LIQUID ALOX may render the muzzle velocity to become slightly more uniform.


2) Some Russian "forest cartridge plants" on the areas occupied by Germans during the Second World War applied this method: to sprinkle mist-like solvent on the powder charges. Just some batches of the Partizanniy cartridges had "lacquer bound" charges. This method is too sensitive to become popular. A slight over-dose of the solvent may spoil the powder, and some more moistening may deteriorate also the primer.

The solvent must be applied as a mist or fog; not as drops or even the droplets. Russians used ether-alcohol (1 : 3 or 4 parts by weight; "Hoffmann's Drops") or acetidine (ethyl acetate) as a solvent of nitro-cellulose powder - or acetone, when available. Pure acetone (NOT the OILY Nail-polish Remover !) is a good general-purpose powder solvent, able to gelatinize also the double-base powders like HODGDON HP-38 or CLAYS. Russian "SOKOL" shotgun powder (or it's predecessor) is flake kernelled like CLAYS, but the flakes are lesser in size and irregular in shape. I presume, this solvent-binding method is applicable to the flaked powders only.

Today we have materials like Dacron-fiber available for use as an over-powder wadding. Russians had not these luxuriances during their "Great Patriotic War" in 1941 to '45..! So, let's enjoy results of modern science, and forget some makeshifts of past times. It takes just few seconds to fill a cartridge case with the fluffy Dacron wadding, while it took sometimes a week to wait and let the solvent to evaporate away, until the lacquer was hardened and the bullets could be seated.

That solvent/lacquer method was known also in Germany during the 2nd Big War, but Germans never didn't adopt it. Their Nz.Pl.Patr.R.P. 1.5 x 1.5 x 0.75 was igniting easily enough to use in 7.9 mm Mauser Nahpatronen without wadding or other means to keep the charge in the rear end of cartridge case. Just blank-cartridges had blotting-paper wad behind a hollow wooden bullet, weighing ½ gram. Apropos: That German blank-cartridge powder "Sorte 33" was a paragon of Finnish VV N 320 (then N 22) in mid-1930s.

Once upon a time Germans tried some kind of cardboard filler, but found it soon unnecessary. According to some German researchers, Russian partizans designed those 7.62 mm Mosin cartridges for shooting muzzle downwards from the trees, close to the roads, to kill some German soldiers sitting on the trucks/lorries. They didn' use suppressors at all, as the roar of truck or tank engines was louder than snappy "CRACK" of a rifle. Germans usually didn't notice that they were targets of shooting "kukushka" (= cuckoo: a sniper, lurking in a tree).

Ignition of the loose powder (especially SOKOL) is regular and efficient even when the charge is in the bullet end of a cartridge, if it is adjusted into the front end of case each and every time. "The name of the game is THE SAME" when the charges are reduced to subsonic level. The hot and broad flame of big Berdan Nr. 1 primer - with diameter 6.45 mm - was able to reach every kernel of the powder charge in a 7.62 x 54 mm case. Primer pocket has two "vent holes" instead of that one concentric flash hole of Boxer priming pocket.

It is possible to enhance ignition of reduced charges by use of powerful Magnum primers. FEDERAL No. 215 is, as far as I know, "hottest" one in the Large Rifle Boxer class. You may also prepare some cartridge cases for use with reduced charges (ONLY) by drilling that flash hole through primer pocket bottom up to the diameter 4.0 or 4.5 millimeters. After these preparations is ignition of .308 Winchester cartridges at least as efficient as that of 7.62 mm Mosin cartridges with largest Berdan primer. Use of over-powder wadding is thereafter unnecessary.

Prepared cases are good for loading of "Cat's Sneeze" indoor practise cartridges with heavily lubricated BORE-sized lead bullet - spherical one, like American No. 1 Buck or British Special L.G. buckshot, with diameter 7.62 mm or .300". Yoy do not need powder at all, as there is no bore friction. Bullets must be lubed heavily with so sticky lubricant that the lube keeps them in the case necks. Beeswax, softened with 25 % addition of LEE Liquid Alox, is a good lube for "Kissan Aivastus" loads, popular in Finland during early 1930s. When you'll get a suppressor, you may surprise your friends by truly silent shooting with "cat's sneezes". A click of rifle striker behind an empty chamber is more noisy than is a report with a cartridge..!

APPENDIX:

Re SAKO TRG-41 in Finnish Army use: Army has bought 300 or 400 rifles. Muzzle of ONE rifle is threaded for T8 Magnum suppressor. Some test-shootings are done successfully. TRG-41 is thought as a long-range sniping rifle. So I don't believe that Army is interested in .338 La.Ma. subsonic loads.

23071999 PeTe



Sako Silencers

Dear Sir,

I have just ordered a Sako Silencer for my TRG-21 .308 rifle.

1) Do you have any drawings or details of this silencer ?

2) The rifle has 1:11 twist rifling. Can you suggest a good subsonic load for it ? I can get bullets from all major manufacturers (LAPUA, SIERRA, etc...) but the choice of powders in New Zealand is a bit limited. We can get all Hodgdon's and ADI (both from Australia) but only Vihtavuori N 320. Is this usable instead of N 310 ?

3) Do you have any data on the Trials of the Finnish Army doing on the Sako TRG-41 .338 La Ma rifle and the silencer they are using in these trials ? I am looking at ordering a TRG-41 from a gunshop in Finland (riistamaa.fi). Any information would be helpful.


P.S. Yes, I read the item Arcane parts 1-3, and the Q/A, as a matter of interest. In New Zealand there is no restriction or licensing. You can walk into a gunshop and buy a silencer over the counter, just as ice-cream. Most of them are made for the .22 LR rifles, being cheap and simple. Main use is at night to shoot rabbits and opossums and not waking up or otherwise disturb your neighbors. Some silencers are even made of plastic PVC tubing, with single chamber. They are very light in weight. The same PVC tubing is used in sinks, etc...

Chris from New Zealand.

1) I am sorry ! SAKO Oy has not replied to my letters or other messages since early 1980's. I am unable to get information on SAKO silencer. You must ask it from "riistamaa.fi".

2) Please, look more carefully at reloading tables of ARCANE series. Shooting trials were done with VIHTAVUORI N 320. Charges of HODGDON HP-38 or UNIVERSAL/CLAYS are similar to those of VV N 310. ("CLAYS" universal powder is actually made in Australia, but the brand-name is presumably different there. HODGDON has not own powder mill. Powders are made by U.S. or foreign manufacturers, like Nobel plants in Scotland). I presume, a SIERRA 110 grains FMJ bullet is good for night hunting, when loaded with 0.35 to 0.40 gram of N 320.

Accidental doubled charge is somewhat noisy but not yet dangerous. Maximum charge for .308 Winchester with 110 grains SIERRA roundnose bullet (designed for U.S. M1 Carbine) is ca. 1.1 grams of Vihtavuori N 320. Some Finnish competition shooters load actually their .308 cartridges with the bullets mentioned and a charge "12 grains of rapid shotgun powder" for "zero meters per second muzzle velocity variation" - needed for the shooting on the moving targets, looking like a moose (= "ALCES ALCES" = big Finnish or Alaskan/Canadian elk).

LAPUA bullet S374 (pointed FMJ, weight 8 grams) is also good for this purpose mentioned, but jacket material of SIERRA 110 gr RN/ FMJ shall give more uniform bore friction, because of less variable hardness of the Gilding Alloy. (Jacket of S374 is of brass; good for supersonic loads but not so good for subsonic cartridges. Actually just swaged or cast and lubricated lead-alloy projectiles are entirely good for subsonic rifle handloads).

3) As far as I know, those Finnish Army trials are interrupted because of the improper mounting of a muzzle brake or recoil compensator on the TRG-41. Mounting of a suppressor is difficult or impossible mission on the muzzle of .338 La.Ma. rifle with a press-fitting and pin only. A thread on a barrel muzzle is essential, due to the high power / muzzle pressure of this long-range sniping cartridge.

The "telegraph operator" of GUNWRITERS websites may presumably add here a sectional drawing of the so-called Telescopic Reflex Suppressor (one of it's variation is designed exclusively for TRG-41 rifle with a threaded muzzle), found from our illustration archives. (I am just a copywriter, able to write text only. My partner has equipment needed for illustration of written material and for "broadcasting" it to the web. I have not even the Internet or E-mail connection to my home, and I've not yet seen my stories from the screen, but some of them as "hard copies"; i.e. paper prints. They're looking good when printed, but - "relata refero" - they look still better on the computer screen.

If Finnish Army is unable to get TRG-41 rifles with mounting thread on the muzzle, they may buy rifles from A.A.I.; England.(A precedent was the choice of a sniping rifle for Swedish Army: Rifle of ACCURACY ARMS Inc. was good but not overly expensive, and ALL the wishes of would-be buyer were put into the practice).

Finnish Army personnel seems to be interested in T8M (T8 Magnum) suppressor because of it's construction, rugged enough for the military use on a long-range sniping rifle like TRG-41. Those suppressors are made also for 12.7 x 99 mm (.50 BMG) rifles, and it seems to be possible to make T8M for truly big sniping guns, example given: For 20 x 138 mm anti-tank rifles. A usual muzzle-can of "LAHTI's Tank Killer" must have size of an oil barrel (159 liters), while T8M might be much smaller. There are, actually, calculations made for 20 mm sniping rifle silencer design - and for subsonic 20 x 138 mm handloads too.!




The practical "upper limit" of subsonic cartridge's caliber is, however, 14.7 mm or about .60 inch. Bigger bullet is noisy in flight - even when subsonic. There are made some suppressors for 12 gauge shotguns, but performance of them is just fair. It is easy to suppress the low-pressure muzzle blast of a shotgun, but the flight noise of a shot load is impossible to completely eliminate, unless the flight velocity is less than 150 meters per second. A triple-zero buckshot load might be efficient to the range less than ten meters.

Americans tried "silent shotshells" during Viet-Nam conflict, but they found performance of them too limited, in spite of lack of the muzzle blast. The powder gasses of A.A.I. Telecartridges were trapped into an iron container in the shotshell. When compared with these "big irons" shall .338 La.Ma. TRG-41 become easy to suppress. One friend of mine is developing a subsonic handload for his TRG rifle. Research is going on despite of retarded Army trials.

P.S. Jess; I know the potential performance of single chamber silencer. I made one in mid-1970's. It was neither small, nor light in weight, but it was efficient - a true silencer - if the .22 LR cartridges were subsonics. Czech Sellier & Bellot "REX" LR cartridges were; .22 Short S & B's were not. Shooting of Shorts was as noisy with or without silencer. That 8 mm bullet passage of my silencer was made by shooting a bullet through wooden end-cap and gimletting the hole more large. Eccentric passage was essential because there was no option for scope mounting for my "Mauserlein" rifle: "JOHA Präsizions Karabiner".

"Defy Lex Morgenthau - do it yourself!" A single chamber silencer, eccentric (as much as it's designer) by P. T. Kekkonen. Sample made in 1975 or '76. About in the time of this design Siegfried Hubner patented a similar silencer in Switzerland. Being concentric might Hubner's silencer have been less efficient?

Also I have made some suppressors from PVC tubes. They had plastic baffles (lathe-turned, of Nylon bar) and aluminum spacers. They were bayonet-mounted on Russian TOZ-8 rifles, .22 LR, having non-tapered barrels with a front-sight mounts strong enough for purpose.

That slogan of mine: "Defy Lex Morgenthau - Do it yourself" on my crude drawing is for American web visitors. One Henry Morgenthau was in 1934 a creator of Federal Firearms Act in U.S.A. Actually it was a "Firearms Taxation Act", needed for financing of F.D. Roosevelt's "New Deal" - but all those taxation laws or acts, planned to be provisional, are after all the remaining scourges. The Great Depression was passed, but Lex Morgenthau remained - along with a disrepute of F.D. Roosevelt as a: "man who NEVER told the truth !"


15071999 PeTe. (Not a Sir, because not a Briton and definitively not a member of The Aristocracy).




Dimensions for AK Suppressor

I need the outer dimensions for PBS3 and PBS4 suppressors so I can make some dummy tubes. Line drawings would be great if available.

Thanks

Martin

  The Russian sound suppressor PBS (Pribor Besshumnoy Stryelbiy = Device for Noiseless Shooting) is designed for subsonic ammo. Sufficient gas pressure to operate Kalashnikov's action with low power subsonic rounds is provided by trapping part of the barrel pressure behind an elastic self-sealing rubber wipe in a high pressure chamber situated in the bore and between the muzzle and the wipe. The pressure bleeds out of the high pressure chamber through pressure relief apertures slowly enough to provide ample push for the gas piston to complete ejecting and feeding cycle with subsonic ammunition. High pressure jets escaping the high pressure chamber are muffled in an expansion situated coaxially around the muzzle and finally led out through exhaust holes. The rubber wipe is followed by regular low pressure expansion chambers separated by straight disc style baffles to suppress the gases escaping behind the bullet when the pressure is high enough to open the self sealing hole of the wipe.

The image above has been drawn to scale. The PBS has been introduced quite thoroughly in the IRSAIS newsletter: Small Arms World Report, Volume 8, Numbers 1 & 2 by Alan C. Paulson, author of  the Silencer History and Performance series of books. See also a drawing of the Finnish KRS (Kalashnikov Reflex Suppressor).

04.07.1999 J. Hartikka




Subsonic .308

I just visited your website for the first time and very happy to see the length you go through to answer questions for those that ask for help. I am one of those that need your help. I just purchased a Remington 700 pss .308 tipped with an A.W.C. Thundertrap suppressor. When shooting match ammo it sounds like a .22 and has the recoil of a .222. I want to know if you can tell me any type of subsonic ammo I can get either commercial or handloads that will stabilize in the 1:12 barrel that I have.

I personally do not reload but have friends that do and could possibly have some produced at a local ammo manufacturing company if I can find one that will stabilize and not "bore out" the baffles in my suppressor. I have heard of Black Hills, but I am not sure of the loads it is offered in. Any help would be greatly appreciated. I live in Georgia, U.S.A. and have had to wait for three months for the suppressor so please help me if you can.

Thanks, Chuck

  Dear Chuck ! You are presumably still ignorant of my articles on reloading of 7.62 mm MOSIN-NAGANT, and (especially) .308 Winchester ? I have titled this information as "ARCANE part I and II", and the story may be still continuing. We have two "GUNWRITERS ON THE WEB" periodicals waiting for text, one in English and other in Finnish. Story of SUOMI model 1931 submachine gun is just now half-done (part 4. of KP/-31 article in Finnish. That version shall become as long as a thin textbook, if finished sometimes).

Many thanks for the information on your REMINGTON. Knowledge on the rifling twist is especially needed for the adviser of handloading. There are some factory-loaded subsonic cartridges loaded with excessively heavy (= long) bullets, unable to become gyro-stabilized in 12" rifling twist but good for .308 rifles with 10" twist (See also chapter "Shooting" in  T8 on-line manual). To additional misery: Some "subsonic" factory-loads are not actually subsonics in all firearms and all temperatures below +21 degrees. Centigrade of test-shooting laboratory. I cannot understand, why those "subsonic" factory cartridges are loaded at all...

I prefer handloading of subsonic cartridges over factory-loads because every rifle or .308 pistol is individual, developing the muzzle velocity exclusively. Loads must be "tailor-made" for each & every bore, or it is essential to adjust the powder charge to give average muzzle velocity less than 950 feet per second from a factory test-barrel, length 24 inches..!

Cast or swaged lead-alloy bullets are the very best projectiles for .308 subsonic cartridges. They'll develop least possible variation of the muzzle velocity, when sized and lubricated properly (usually to .309" diameter) and seated to the cases almost "dry". (Slight oil-coating may be necessary when pushing the bullets through resizing die, but it is advisable to lubricate that DIE and not the BULLETS !). This means NOT shooting of them un-lubricated, of course, if the bore of your rifle is not lubricated before each shot.

When the cartridges are re-primed, charged with powder and bulleted, are the bullets lubricated by dipping them into the molten wax-lube, or LEE LIQUID ALOX (thinned with a "lamplight oil" = kerosene, if necessary). Circa 1 to 2 millimeters of a case mouth must also be dipped into the lubricant. A "capillary suction" shall imbibe the lube into the seam between bullet and case neck, sealing it properly and lubricating bullet's shank too; not it's point only. It is also advisable to lubricate jacketed bullets with similar method, if suitable lead-alloy slugs are not available !

My "pet bullet" for .308 is LEE 311-93-1R, but it may be too light for many special purposes. Cast bullets with a weight up to 160 grains are O.K. for your rifle. If they are heeled for use of a gas check, you CAN use gas checks. They improves the accuracy of lead-alloy bullet, if checks are properly fixed-on.

Those, made by HORNADY, have a "crimp-on" construction. LYMAN checks needs gluing-on with a drop of epoxy glue, but they are good for bullets, shootable "as cast", without resizing . (Examples: LEE .309 bullets of rather soft alloy, like 70 % lead + 2 % tin + 28 % wheelweight alloy). That fixing of the gas check is ESSENTIAL, if bullets are shot through a suppressor/silencer of any kind !!!

Maximum advisable weight of jacketed bullet for .308 Winchester rifle with 12" rifling twist is as small as 150 grains, and the bullet must be flat-based & round-pointed. Jacketed bullets weighing less than 90 grains are, on the other hand, too light for .308. (Russians loaded 72 gr. bullets for their 7.62 mm Mosin's "hunting cartridges", but these "brass pills" were shaped and dimensioned exclusively, being over-sized at point).

Pointed bullets, weighing ca. 123 grains, are O.K. but a "half jacketed" SPEER PLINKER gave very good accuracy in my tests of subsonic handloads, and those 100-grainers are presumably very inexpensive projectiles in Georgia. (Not in Finland...) Some experimenters have found 110 grains FMJ roundnose bullets good for .308 subsonic loads. Especially Sierra bullets have very consistent bore friction and good accuracy - despite of the fact that 110-grainer FMJ RN is intended for the U.S. M1 Carbine; not so very accurate piece of equipment itself, but there are THOMPSON-CENTER CONTENDER pistols chambered for M1 Carbine cartridges. Users of them insists on the accuracy..!

Powders of your subsonic loads, for the suppressed/silenced rifle, must be as easily igniting and as quickly burning, as available..! (I cannot use the phrase: "as possible", because production of those good old & reliable "Bulk Shotgun Powders" has been discontinued more than half of a century ago). Finnish Vihtavuori N 310 seems to be very-best-of-the-world propellant for the subsonic rifle cartridges, but HODGDON's HP-38 and CLAYS are also good for these special loads ..!

(Why not "BULLSEYE" or "RED DOT "? They are presumably good powders too, but they are unavailable in Finland - and no printed source of information is published with useful charges of them for subsonic cartridges. Not even in those many "Cast Bullet Reloading Handbooks" in my book-shelves. Handloading of subsonic rifle cartridges seems to be a "Black Magic" or "Taboo" all-round the world. Not only in Finland..).

Loading of .308 cartridges for use in a suppressed/silenced rifle is a funny job, compared with usual handloading: Loads are usually "stepped up" from a "Suggested Starting Load" of a Reloader's Manual or Handbook, until Maximum Charge or until the shell (cartridge case) can hold no more powder, or until the signs of excessive chamber pressure. (Your handloading friend presumably knows these fundamentals).

Handloading of subsonic rifle cartridges starts also from the "Suggested Starting Load" (= usually ½ grams or 7 ½ grains of powder VV N 310 or HP-38 or CLAYS. This charge has NEVER exploded a .308 Win. rifles, but HALF of this charge may do it when topped with a heavy jacketed bullet..!! Behind a cast bullet LEE 311-93-1R is 3 grains charge good, safe and subsonic, but unfit for loading with jacketed bullets; any kind of them - including SPEER "PLINKER"..!).

The charge must become usually "stepped down" until that nasty "whiplash noise" or "supersonic crack" is no more audible, and still one more "step" downwards.(A "step" is usually 0.02 gram or 0.3 grain of powder. I prefer powder dosage by volume, not by weight, and I "steps down" the powder charges by filing my "do-it-yourself" powder dippers more shallow. They are made from empty handgun shells. "The extreme poverty is a mother of utmost inventiveness !"

LEE POWDER MEASURE KIT's scoops are also very useful, if the needed powder charge fills one or two dippers evenly. Example given: A charge 0.4 gram of N 310 for .308 Winch. with 110 grains SIERRA FMJ RN. Weight/volume ratio of powder is ½ gram per cubic centimeter. 0.8 CC dipper is not in the KIT. If I needs a small batch of cartridges for test-shooting, I'll use two dippers: 0.5 CC + 0.3 CC = 0.8 CC. For the need of more cartridges with this volume of powder, I'll make a dipper from an empty pistol shell. NOTA BENE: 0.7 CC of powder N 310 is a good subsonic charge for some .308 rifles, along with SIERRA's 110 grains RN FMJ bullet. LEE MEASURE KIT contains a .7 CC dipper).

Sonic velocity in the ambient air depends on air temperature. Those loads developed in the hot day in summer may cause nasty surprises in a frosty winter climate. (If you have fifty extra dollars, you may use them sensibly by buying a book:"Silencer History and Performance, Vol. 1" by ALAN C. PAULSON; publisher Paladin Press. 0n it's pages 397 to 400 are very interesting tables "SPEED OF SOUND V:S TEMPERATURE" and "Bullet  flight  noise at varying velocities". In Georgia may the puddles be frozen in some frosty mornings ? In Finland there were 60 degrees. below zero F = 51 degrees b.z. Centigrade temperatures officially measured in February 1999. Sonic velocity was mere 980 feet per second !).

The Name of a Game is the Same: Use always same brands of empty cases, primers, bullets and powder for your subsonic loads, when you (or your handloading friend) have found a proper, accurate combination of loading components for your rifle. An outsider/ adviser is unable to give exact information for loading of cartridges, but just some elementary rules of general application.

Please, take you time for visit on the "ARCANE" sites ! They are crammed full of Finnish less-known history, stories on our more or less celebrated National Heroes, et cetera..! ARCANE Part II contains some loading tables for .308 Win. cartridges. Arcane part 1 URL is: http://guns.contact.fi/gow/arcane1.html

Good luck for loading project !

18061999, sincerely yours: PeTe



Cats Sneeze for .223

I loved your article!  I learned a lot about Finland and freedom as well, not just about light loads.

Would Russian Boattailed 62 grain .223 work well subsonic if reloaded with 1/2 charge of the same powder and the bullet inserted backwards?

D. S.

  I presume, this bullet is too long to become gyro-stabilized in the bore of your rifle. Rifling twist must be less than 1 in 7" or the rotational rate may become too low. This very bullet has a long empty point and majority of it's core is of steel.

According to the old GREENHILL's Second Formula of stabilizing it is essential to made bullet core of heavy material (lead is O.K., tungsten is better and uranium still more better) or use shorter bullets. Those with aluminum cores are never very long when compared with diameter.(They were made in Germany and more recently in Finland too. Now-a-days discontinued, because of an ability to perforate bullet-proof vests "too easily"..!)

If the cross-sectional density of a projectile is low because of low specific gravity of materials used (mild steel jacket and steel core, along with a void inside the bullet point) it is essential to enhance the rotational speed by adoption of very "steep" rifling, as the Russians were done.

Those real "Cat's Sneezes" did have spherical bullets of the bore diameter. Spherical lead pill needs actually no rotation at all to be sufficiently accurate to ranges ca. 10 meters. That Russian 5.45 mm bullet with a nominal diameter .218" may exceed the bore diameter of your rifle and so start to spin. When rotating, it starts also to yaw during it's flight. According to the "gray theory" may a base-heavy bullet (like this Russian one) fly like an arrow, when propelled base-on, if it does not gain rotation in rifling. It needs, however, some kind of finned tail - just like an air-dropped bomb or a mortar shell - and a diameter slightly less than the bore dia. And those 5.45 mm bullets, I afraid, are not thin enough..! They shall rotate - and yaw - even if "fin stabilized"

Shooting of overly long bullets seated backwards will usually not improve it's stability in flight. Sometimes may a bullet be marginally stable, when seated point-on but unstable when shot base-on. Boat-tail FMJ projectiles (like .308 LAPUA D-46, weight eleven grams) are equally accurate at short ranges when seated base-on, but some hollow-point projectiles may tumble after a short flight. Old SIERRA 190 gr. "MATCHKING" did so, when shot from a bench-rest rifle (.308 Win.) with 12" rifling twist. Another rifle with 10" twist was able to stabilize it, when seated point-on but the holes on a target were slightly drop-shaped, when those bullets were propelled base-on. Accuracy was almost equal but yawing bullets lost velocity and energy sooner than those, shot point-on.

Because maximum allowed velocity of subsonic bullet isn't much more than 1000 feet per second, it is advisable to prevent any unnecessary loss of velocity. According to the very most recent studies is pointed projectile with a boat-tail O.K. for subsonic velocities too. The gain of backwards seated bullets is lost easily if they shall yaw during the flight. (That more or less theoretical gain comes from reduction of a "suction air resistance" behind the projectile).

If I understood your message correctly, you are planning to use ½ charges of RIFLE powder salvaged from Russian 5.45 mm factory-loaded cartridges..??!! Please, DO NOT TRY IT !!! This Russian special powder is unknown stuff to all friends of mine, and to me, of course. It is a RIFLE powder, however, and contains a percentage of explosive known as DNT (Di-Nitro-Toluene). If nitrated to somewhat higher degree, this same stuff is known as TNT. And this nitration may happened in the gaseous phase, causing a phenomenon called as a "Secondary Explosion Effect" or a "Reduced-Charge Detonation (S.E.E. or R.C.D). Nobody knows, how prone this Russian powder is to detonate, when loaded with ½ charges. It is never sold as canister powder to reloaders but just to the ammunition plants for factory-loading of full-power cartridges.

As you have seen, I have always recommended use of as easily igniting and rapidly burning powders for loading of subsonic cartridges, as available now-a-days; those ones like Hodgdon HP-38 or Clays, or Vihtavuori N 310. (Best ones, those Bulk Shotgun Powders, are unfortunately no more available...) As a Suggested Starting Load for .223 I have recommended 50 grains or 55 grains bullets and a charge of spent .22 Long Rifle cartridge case full of VV N 310. This charge has usually been subsonic, and many times accurate too.

Reloader himself must fine-adjust one's "optimum charge" for his/her rifle if necessary for seeking after the accuracy but not yet exceeding the sonic velocity. Most Finnish reloaders are seeking special loads for rifles equipped with a silencer or suppressor, but subsonic loads are useful in non-suppressed rifles too. Skill of "Cat's Sneeze" or "Gallery Cartridge" handloading is MORE needed in the countries (like U.S.A.), where possession of firearms silencers is restricted. In Finland is buying of a suppressor more easy than acquiring a box of cigarettes or a bottle of beer with 4½ %-vol. percentage of ethanol. Nobody asks questions like: "Are you 18 years old ? Show your ID-card, please !"

For the reloading advisers - like me - is .223 a nightmare, as there are too many different kinds of rifles with exclusive twists of rifling, from 1 in 16" to 1 in 7½" or so. Those old military calibers like 7.62 mm Mosin & 7.62 mm Yelisarov-Syemin (both Russian), 7.9 x 57 mm Mauser or .30-06 are like a sweet dream: Every rifle has similar rifling twist, and that twist is sufficiently steep or "fast": 1 in 240 mm or 254 mm (ten inches) in .30-06.

True .223 Cat's Sneezes are possible to load with spherical lead bullets with the diameter 5.50 millimeters (now-a-days available in Finland; imported from Spain) and Small Rifle Magnum primers, with or without a very small booster charge of N 310. One may cast his/ her slugs. LYMAN N:r 225 415 is good for .223. Nominal weight is 45 grains. Suitable powder charge is that same .22 Long case full of Vihtavuori N 310 or HP-38 or "Clays". (Charge weight ca. 3 grains of N 310). These bullets are for the "Gallery Loads" or "Partisan Cartridges", but not the true "Cat's Sneezes", being groove-sized and pointed.

I presume, some four grains of N 310 may be a safe Starting Load for .223 with Russian 5.45 mm bullet, but nobody knows, whether or not that projectile is able to fly straight. More information on your rifle (autoloader or bolt-action ? Twist of the rifling ?) is needed. I don't know even your demand of shooting accuracy or the range: One foot or 100 yards ?

Joensuu, Finland, 1406199, yours sincerely: PeTe

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