(Don't use snap caps as dummies they don't duplicate loaded round weight/balance.) Mfg.. The spring loaded "primers" in these snap caps act much like a live primer and cushion the deluxe snap cap 243 2 caps per pak blow so firing pin and bushing damage won't occur. Bright color and "different" feel to prevent deluxe snap cap 38 6 caps per pak mixing with live rounds or function testing dummies. Bright color and "different" feel to prevent mixing with live rounds or function testing dummies. (Don't use snap caps as dummies they don't duplicate loaded round weight/balance.) SPECS. The spring loaded "primers" in these snap caps act much like deluxe snap cap 44 6 caps per pak a live primer and cushion the blow so firing pin and bushing damage won't occur.