In the book Into the Wild Chris McCandless took nothing into the Alaskan bush but a 10 pound bag of rice and a .22 rifle.

The low cost, minimal recoil, and relatively low noise make the .22 LR an ideal cartridge for recreational shooting, initial firearms training, and pest control, and it is often purchased in bulk. The round is popular among novice shooters and experts. .22 LR is commonly packaged in boxes of either 100 or 50 rounds, and is often sold by the brick, a carton containing either 10 boxes of 50 rounds or loose cartridges totalling 500 rounds, or the case containing 10 cartons totalling 5,000 rounds.
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Virtually every manufacturer of cartridge firearms makes at least one model chambering it, and this has been true for more than a century. The .22 Long Rifle and related cartridgesuse a heeled bullet, which means that the bullet is the same diameter as the case, and has a narrower "heel" portion that fits in the case.The accuracy of the cartridge is good, but not exceptional; various cartridges are capable of the same or better accuracy. A contributing factor in rifles is the transition of even a high-velocity cartridge projectile from supersonic to subsonic within 100 yards (91 m). As the bullet slows, the shock wave caused by supersonic travel overtakes the bullet and can disrupt its flight path, causing minor but measurable inaccuracy

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As a hunting cartridge, the .22 LR is mainly used to kill small game such as ratsand squriels. It is also highly effective on rabbits at distances closer than 150 yards (140 m) and on ground hogs, marmots, and foxes closer than 80 yards (73 m). It has been successfully used on large creatures such as coyotes, but range should be limited to no farther than 65 yards (59 m); head and chest shots are mandatory with the most powerful .22 cartridge the hunter can use accurately.
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.22 Long Rifle bullets are generally either plain lead (for standard velocity loads) or plated with copper or gilding metal (for high velocity or hyper velocity loads). The thin copper layer on the bullet functions as a high velocity lubricant reducing friction between the bullet and the barrel, thus reducing barrel wear. It also prevents oxidation of the lead bullet. Lead tends to oxidize if stored for long periods. Oxide on the bullet's surface could increase its diameter enough to either prevent insertion of the cartridge into the chamber, or - with hyper velocity rounds - cause dangerously high pressures in the barrel, potentially rupturing the cartridge case and injuring the shooter.