Our ingenious Auto-PopperA(R) also comes in a lighter weight version for use with .22 caliber rimfire arms. This target is designed the same as our standard Auto-PopperA(R), but has a lightweight spring that allows the target to react to the .22 bullet. The target itself is A 1/4" 400 Brinell steel. The .22 Auto-PopperA(R) is available in the standard shape as well as a ground squirrel shape. These targets are great for kids! Mfg: Mgm Targets