My first pig as an 11 year old was with a single shot .22, a 50 pound straggler in a big mob that ran past my father and I, instant kill neck shot at about 20 yards. Since then I have found .38 S&W, .223, 7x57, .30 M1 Carbine, .303, .308, .30/06, .44 Magnum, and .45 ACP have all done the job nicely, albeit under differing conditions. No calibre is perfect for all conditions but in terms of number of animals shot, .303 and .30/06 have been the best in my experience, although I once shot 14 pigs in one mob with 15 shots from my FN FAL (back in the days when we were trusted with such things!).
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