Rounds for a .22 caliber rifle are by far the most common ammunition in the world and can be purchased at virtually any retailer of firearms in the United States. Walmart sells bulk quantities of .22LR made by Federal Ammunition in value packs of 550 rounds.
The .22 long rifle cartridge was developed by American firearms manufacturer J. Stevens Arms &; Tool Company in 1887. The cheap price, light recoil and low noise make the round popular for primary firearms training, recreational shooting, small game hunting and pest control. It is estimated that 2 billion .22LR rounds are manufactured every year.