Читать книгу The Gun Digest Book of .22 Rimfire. Rifles·Pistols·Ammunition онлайн

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With all of these developments and those described in the following sections, there can be little doubt that this is an exciting time for the rimfire shooter. More details on the performance of today’s rimfire cartridges will be presented in several later chapters in this book.

22 Winchester Magnum Rimfire (WMR)

As wonderful as the 22 LR is, there are situations where more power is called for. In 1959, Winchester responded to that need by developing a cartridge that utilizes a case that is 1.05 inches in length and has a slightly larger diameter head and body than the 22 LR case (0.291” vs. 0.275” and 0.241” vs. 0.225”, respectively ) . Instead of using a bullet with a heel of smaller diameter that fits inside the case and a bullet that has the same diameter as the case, the new round used a 40-grain jacketed bullet of 0.224-inch diameter. This “magnum” rimfire is appropriately named the 22 Winchester Magnum Rimfire (WMR), and the advertised velocity is 1,910 ft/sec from a 24-inch barrel. With a muzzle energy of 310 ft lbs, the 22 WMR is still the most powerful rimfire cartridge available. From the 20-inch barrel of my Ruger 77/22M, the velocity at 10 feet from the muzzle is below the advertised value by about 75 ft/sec.