Boom Stick
12-21-2009, 08:06 PM
Are the velocity numbers listed in the article below even remotely possible even with longer barrel lengths? This whole article just seems to be blowing smoke in an arse-like direction.
http://home.xtra.co.nz/hosts/suppress/whisper.htm
"The 300 Whisper
The 300,.338 & .510 are the most common JDJ Whisper calibres, but in particular the 300 Whisper deserves attention because of its dual role as a subsonic & supersonic round. Eitherload can be used out of the same rifle without compromising the other. "The 300 Whisper was the first of the series & contrary to what you may & contrary to what you may have read, the cartridge was designed as a multi-purpose cartridge from the beginning", - says JD Jones, the inventor of the Whisper series. While JD Jones' company is a Class 2 or military manufacturer, its proprietor is also an avid hunter who has travelled widely, taking a variety of game with the 300 Whisper- & this with handguns! His preferences are T/C Contender or Encore based single shot pistols. However, due to their short barrel, JD's 12 or 14 inch "hand cannons" may not reveal the full potential of the .300 Whisper.
To compare its sonic preformance with the 7.62 x 39 Russian (as described in books & on internet sites) is a gross understatement, if not simply wrong. Even if not loaded to max, it is better to compare the 300 Whisper supersonic with the .300 Savage or 30/30 Win. The maximium velocities with 125 grain projectiles reaches 2870 fps, 2600 fps with the heavier 150 grain projectiles. More moderate loads in the 2400-2600 fps area & the corresponding energy still make this an excellent deer cartridge out to 250 yards. All this with a very mild (.223 like) recoil. low noise & excellent accuracy - Typically around 1/2 MOA or 0.5 at 100 yards. Even without looking at the subsonic suppressed loads, this combination & preformance makes the .300 Whisper an ideal lady-hunter or youngster's deer rifle - or anybody put off by heavy recoil & the noise level for that matter. By all means it is a better choise than the marginal .223 many of us shot our first deer with! Although the suppressor removes the muzzle blast it is obvious that any supersonic projectile creates a ballistic crack, but this wouldn't be louder than .22 Magnum Rimfire. As the .300 Whisper is based on the .221 Fireball it has the same case head dimensions as the .222 or .223 cartridge & will fit - once rebarrelled & converted to a .300 Whisper - into most lifgt .222/.223 rifle & magazines. The payload for the subsonic .300 Whisper ammunition is preferably in the 240-250 grain weight. Using anything under 220 grains is a waste of time as both energy & "yawing" effect diminish quickly with lighter projectiles. Considering the approximately 1040fps bullet speed needed for subsonic load only the projectile's weight can create sufficient energy. The "yawing" refers to the tumbling of these long 240 & 250 grain projectiles immediately after impact - a major part of the Whisper concept, disreguarded or misunderstood by many. While they are stable in flight, even a cardboard target clearly shows the tendency of these bullets to tumble on impact, thus creating wounds far in excess of their "paper" ballistics. It is futile to look for the magic bullet that expands or mushrooms at subsonic speed - such a thing in a .30 cal sectional density doesn't exist, nor will experiments with cast lead projectiles lead to greatly improved result. However, a hard & solid 240 grain Sierra Matchking turning over lengthwise is equivalent to a seven times calibre expansion! These high ballistic coefficient projectiles retain energy as well as sub MOE accuracy out to 200 yards & more. While the bullet leaves the muzzle at 1040 fps, at 100 yards it loses only 3%, travelling at 1011fps & at 200 yards it still keeps on motoring with a solid 984fps. As velocity is retained, so is the energy; muzzle 576 ft/ibls, 100 yards 544 ft/lbs & 200 yards 517 ft/lbs. Only beyond 250 yards does the energy start to drop below the 500 ft/lbs mark. Comparing this to your standard 9mm or 45ACP pistol Marlin Camp Carbine cartridges, the first one only makes around 230 ft/lbs while the latter 300ft/lbs at 100 yard line. It is no wonder that some military units previously using these pistol calibres in semi-autos or sub-machine guns have switched to the .300 Whisper. while other common military rounds like the .308 or .223 show either over or under penetration, the .300 Whisper accomplishes the job silently & effortlessly. Special purpose projectiles ammunition, so called "helmet punchers" successfully penetrate automobile bodies, a task where almost anything short of a .50 BMG will have the occasional failure."
http://home.xtra.co.nz/hosts/suppress/whisper.htm
"The 300 Whisper
The 300,.338 & .510 are the most common JDJ Whisper calibres, but in particular the 300 Whisper deserves attention because of its dual role as a subsonic & supersonic round. Eitherload can be used out of the same rifle without compromising the other. "The 300 Whisper was the first of the series & contrary to what you may & contrary to what you may have read, the cartridge was designed as a multi-purpose cartridge from the beginning", - says JD Jones, the inventor of the Whisper series. While JD Jones' company is a Class 2 or military manufacturer, its proprietor is also an avid hunter who has travelled widely, taking a variety of game with the 300 Whisper- & this with handguns! His preferences are T/C Contender or Encore based single shot pistols. However, due to their short barrel, JD's 12 or 14 inch "hand cannons" may not reveal the full potential of the .300 Whisper.
To compare its sonic preformance with the 7.62 x 39 Russian (as described in books & on internet sites) is a gross understatement, if not simply wrong. Even if not loaded to max, it is better to compare the 300 Whisper supersonic with the .300 Savage or 30/30 Win. The maximium velocities with 125 grain projectiles reaches 2870 fps, 2600 fps with the heavier 150 grain projectiles. More moderate loads in the 2400-2600 fps area & the corresponding energy still make this an excellent deer cartridge out to 250 yards. All this with a very mild (.223 like) recoil. low noise & excellent accuracy - Typically around 1/2 MOA or 0.5 at 100 yards. Even without looking at the subsonic suppressed loads, this combination & preformance makes the .300 Whisper an ideal lady-hunter or youngster's deer rifle - or anybody put off by heavy recoil & the noise level for that matter. By all means it is a better choise than the marginal .223 many of us shot our first deer with! Although the suppressor removes the muzzle blast it is obvious that any supersonic projectile creates a ballistic crack, but this wouldn't be louder than .22 Magnum Rimfire. As the .300 Whisper is based on the .221 Fireball it has the same case head dimensions as the .222 or .223 cartridge & will fit - once rebarrelled & converted to a .300 Whisper - into most lifgt .222/.223 rifle & magazines. The payload for the subsonic .300 Whisper ammunition is preferably in the 240-250 grain weight. Using anything under 220 grains is a waste of time as both energy & "yawing" effect diminish quickly with lighter projectiles. Considering the approximately 1040fps bullet speed needed for subsonic load only the projectile's weight can create sufficient energy. The "yawing" refers to the tumbling of these long 240 & 250 grain projectiles immediately after impact - a major part of the Whisper concept, disreguarded or misunderstood by many. While they are stable in flight, even a cardboard target clearly shows the tendency of these bullets to tumble on impact, thus creating wounds far in excess of their "paper" ballistics. It is futile to look for the magic bullet that expands or mushrooms at subsonic speed - such a thing in a .30 cal sectional density doesn't exist, nor will experiments with cast lead projectiles lead to greatly improved result. However, a hard & solid 240 grain Sierra Matchking turning over lengthwise is equivalent to a seven times calibre expansion! These high ballistic coefficient projectiles retain energy as well as sub MOE accuracy out to 200 yards & more. While the bullet leaves the muzzle at 1040 fps, at 100 yards it loses only 3%, travelling at 1011fps & at 200 yards it still keeps on motoring with a solid 984fps. As velocity is retained, so is the energy; muzzle 576 ft/ibls, 100 yards 544 ft/lbs & 200 yards 517 ft/lbs. Only beyond 250 yards does the energy start to drop below the 500 ft/lbs mark. Comparing this to your standard 9mm or 45ACP pistol Marlin Camp Carbine cartridges, the first one only makes around 230 ft/lbs while the latter 300ft/lbs at 100 yard line. It is no wonder that some military units previously using these pistol calibres in semi-autos or sub-machine guns have switched to the .300 Whisper. while other common military rounds like the .308 or .223 show either over or under penetration, the .300 Whisper accomplishes the job silently & effortlessly. Special purpose projectiles ammunition, so called "helmet punchers" successfully penetrate automobile bodies, a task where almost anything short of a .50 BMG will have the occasional failure."