While the .22 LR is undoubtedly the most common caliber in the world, it does leave something to be desired in terms of effectiveness on anything beyond, say, soup cans and cottontail rabbits. Is it a deadly caliber? You bet it is. There is, however, a distinction between shear lethality and the ability to do so efficiently with rimfire ammunition.
The .22 Winchester Magnum Rimfire (WMR) was designed for just this purpose: provide a hard-hitting .22 using a standard weight .22 LR bullet, and the results have been impressive.
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