I tried some Hornady Critical Defense 00 Buckshot in my M4 today. I only shot 10 rounds of it, but to my surprise I had 3 or 4 failures to eject. The extractor was slipping off the rim of the shell, leaving it about halfway out of the chamber. I fired 50 or so rounds of Winchester and Federal with no other malfunctions and I’ve never had this happen with any other rounds. Only other malfunctions I’ve had has been low recoil rounds failing to cycle, which isn’t too surprising. My extractor appears undamaged on visual inspection. On close inspection of the Critical Defense shells, the rims appear and feel more rounded and less aggressively angled my other shells, even some old Hornady Superformance shells I have on hand (which have functioned reliably). This leads me to believe that the “smoother” rim is allowing the extractor to slip off the shell as the bolt is driven back by the gas system. Goes to show why it’s so important to function test any new ammo in your firearm before trust it potentially with your life, even if it’s considered premium ammunition. Anyone else experience this with Hornady CD?
