As always... look to the Old Timers:
"SILENCE IS GOLDEN!"
By CHARLES E. HARRIS
Many years ago I had occasion to make up some subsonic loads in 7.62 NATO for use in a suppressed M21 sniper rifle, which is based upon the M14. The NATO-type 148-gr. FMJBT bullet is not adequately stabilized in the 12" twist of rifling barrel at subsonic velocities, but the 110-gr. FMJRN bullet used in the .30 M1 carbine cartridge works well and is quiet with 6 grains of Hercules (now Alliant) Bullseye.
The most effective "Silent Without Silencer" rifle I have is an old English "Rook Rifle" which was originally chambered for the .360 No.5. Most of these rifles will fire .38 Long Colt ammunition without alteration, but I have found it much better to rechamber them to use .38 Special. Standard velocity 148-gr. hollow-based wadcutter target ammunition is very quiet and accurate, and gives about 870 fps in a 25" barrel. The Marlin 1984 "Cowboy" lever action rifles with 24" barrels are accurate and fairly quiet with ordinary standard velocity 158-gr. lead bullet factory loads which provide about 950 fps. For minimum noise, I handload the factory Remington 158-grain swaged lead SWC bullets with 4 grains of W-W 231 or 3.5 grains of Bullseye for about 850 f.p.s. Below this velocity accuracy suffers due to inadequate bullet stability.
For another quiet combination with available factory rifles and ammunition, use .32 S&W Long factory loads with the 98-gr. lead roundnosed bullet in old rifles chambered for the .32-20 Winchester. These were very popular ranchers and farmers guns in the USA prior to 1940 and are highly prized today by turkey hunters. Standard factory .32 S&W Long ammunition is very quiet and accurate to 50 yards or so, although fired cases swell up a bit.
It is much better to reload a reduced charge of 3 grains of Bullseye in the .32-20 case with the standard 100-gr. flatnosed cast lead bullet which is popular for Cowboy Action Shooting. I use the Ideal Nr. 3118 bullet cast for the .32-20 in the .30-30 Winchester with 4 grains of Bullseye. In old rifles with 24" or longer barrels this is very quiet. Newly manufactured Marlin "Cowboy" guns will give the same result.
IMR shotshell powder "PB," which stands for "porous based" is a fine grained and easily ignited, bulky powder intended for trap, skeet loads and upland game bird loads. This powder burns very similarly to Alliant's Unique or VihtaVuori's N320, which makes it excellent for subsonic loads. For cast lead plainbased bullets weighing from 100 to 130 grains, a charge of 4 grains of PB works provides subsonic velocity in .32-20 rifles, and 5 grains in the 7.62x39, 6 grains in the .30-30, and 7 grains in the .303 British, 7.62 NATO or 7.62x53R. If jacketed bullets are substituted, it is absolutely necessary that the bore be thoroughly cleaned, lightly oiled, the bullets themselves lightly lubricated by tumbling in Lee Liquid Alox, and these charges also increased by 1 grain, across the board.
C.E. Harris
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