CCI 0012 Standard Pistol No. 300 Large Pistol Multi Caliber Handgun 1000/BoxCCI's primer is more sensitive, easier to seat and more compatible with progressive and automated loading equipment than even before. CCI standard primers are remarkably clean burning, leaving primer pockets cleaner and extending the time between pocket cleaning. This primer is compatible with large pistol calibers like 10mm Auto, 44 Rem Mag, 45 ACP and more.