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

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However, there is a potential problem with simply changing the barrels on 22 LR semiautomatics. The new 17 Mach 2 burns more powder than a 22 LR so the chamber pressure remains high for a longer period of time. This causes the bolt to be driven to the rear at higher velocity than when 22 LR cartridges are fired. To keep the bolt from being driven back with enough force to damage the action, a heavier bolt must be used or a stronger recoil spring or both. There is no problem with bolt-action 22 LR rifles becoming 17 Mach 2 pieces, but in the case of autoloaders, changes other than merely switching barrels may be necessary.

Firing a 17-grain bullet with a muzzle velocity of 2100 ft/sec, the 17 Mach 2 produces a muzzle energy of 166 ft lbs. This is less power than that produced by some high performance 22 LR rounds so the 17 Mach 2 is a rifle for small pests. Accuracy as good as that produced by any rimfire is the strong point of the 17 Mach 2. With its flat trajectory, small pests are in danger out to around 125 yards when the shooter does his or her part. However, two of the last three boxes of 17 Mach 2 ammunition that I bought cost $6.99 each while the other was $5.99. This is approximately two or three times the cost of good quality 22 LR ammunition and is about the same as 22 WMR ammunition. The difference probably would not matter to a pest hunter, but it certainly would to the casual plinker.