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The .327 Federal Magnum is a cartridge introduced by Sturm, Ruger and Federal Cartridge, intended to provide the power of a .357 Magnum in six shot, compact revolvers, whose cylinders would otherwise only hold 5 rounds. The .327 Federal Magnum is actually a super magnum having replaced the .32 H&R Magnum as the pinnacle of the cartridge diameter. In the April 2008 issue of the NRA's ''American Rifleman'' magazine, Field Editor Bryce Towsley summed up his review of the cartridge as follows: The cartridge ultimately won the NRA Publications's prestigious ''Golden Bullseye Award'' for "Ammo of the Year" (2009). ==Background and Cartridge Development== First introduced by Federal Cartridge company, the .327 Federal Magnum is an attempt to improve on the .32 H&R Magnum introduced in 1984. Like the .32 H&R, the .327 Federal Magnum is a lengthened, magnum version of the original .32 S&W cartridge, which dates back to 1878. The .32 S&W was a black powder cartridge developed by the Union Metallic Cartridge Co. (UMC) with a case length of 0.61 in. (15 mm), and developed a velocity of around 700 ft/s (215 m/s).〔See main article, .32 S&W〕 In 1896, the .32 S&W Long was introduced, which had a case length of 0.920 in (23.4 mm) and generated slightly higher velocities.〔See main article, .32 S&W Long〕 The introduction of the .32 H&R Magnum nearly a century later increased the case length to 1.075 in (27.3 mm) and increased pressures from 15,000 psi to 21,000 CUP, giving velocities of approximately . However, the .32 H&R cartridge failed to attract much interest from gun owners.〔See main article, .32 H&R Magnum〕 Based on the .32 H&R Magnum, but with a 1/8" longer case, a strengthened web at the base of the case, thicker case walls, and different heat-treatment and metallurgy, the .327 Federal Magnum can be loaded to much higher pressure levels (45,000 psi) than its predecessor (21,000 CUP).〔Pearce, Lane, ''Reloading the .327 Federal Magnum'', Shooting Times Magazine, 4 January 2011〕 The .327's actual bullet diameter is .312 in, or 7.92 mm, and achieves velocities up to with bullets (420 m/s and 6.5 g), and up to with bullets (390 m/s and 7.5 g), when fired from the 3 1/16" (78 mm) barreled Ruger SP101 revolver.〔(Ballistics By The Inch .327magnum results. )〕 With its strengthened case and increased pressure ceiling, the .327 Federal Magnum reaches the velocity levels of the .357 Magnum, if not the same power, with velocities of up to 1400 ft/s (420 m/s) from the 3 1/16" barrel of the first-edition Ruger SP101. Since the .327 Federal Magnum still shares all case dimensions, excluding length, with the .32 S&W, .32 S&W Long, and .32 H&R Magnum, revolvers chambered for the .327 can safely chamber and fire these other cartridges as well. While felt recoil exceeds that of the .32 H&R magnum, revolvers in .327 Federal Magnum are much easier to control than equivalent models chambered in .357 Magnum. Comparing the two calibers, Chuck Hawks says, "There is no doubt that, for most shooters, the .357 Mag. produces uncomfortable recoil and muzzle blast. ATK recoil figures for the .327 Mag. show free recoil energies of . for the 85 grain JHP factory load, for the 115 grain JHP load and for the 100 grain SP load. For comparison, ATK figures are for the 85 grain .32 H&R Mag. load and for the 125 grain .357 Mag. load."〔(【引用サイトリンク】title=First Look: .327 Federal Magnum Revolver Cartridge )〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「.327 Federal Magnum」の詳細全文を読む スポンサード リンク
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