We had a shooter using a Ruger carbine in 40S&W and CCI aluminum case ammo. He had a jam and it turned out the case broke in two parts leaving the base and part of the case (sort of a 40S&W Short) and the upper section of the case making it a short tube. The break was clean and looked like the case had been cleanly cut in half. Has any had a similar experience? Could it have been the carbine creating a slightly higher pressure for a longer period of time? I recomended to him that he contact CCI and keep the box for the lot number. It was purchased that day at Dicks so it was not an old run.

Had a similar incident years ago with CCI Blazer 45 ACP. Case separated at base of bullet. It was shot in a 1911. Back end of case ejected into mag well sending mag out of gun and breaking one of the grips off gun. Head with case still intact around it went down barrel and stuck at muzzle. Sent remaining back to CCI at their request. Got a letter back stating ammo not at fault was most likely gun. They sent a coupon for free box ammo. Used a cleaning rod and hammer to clear muzzle, put new grips on, miked barrel, and been shooting it ever since. Works fine. No problem with brass shells ever since that day. Threw away letter and coupon. Walked away from CCI Blazers and never returned. No injuries that day either.

 

I believe the aluminum case may have been misformed, or the case was damaged somehow during bullet seating. The barrel after this incident was checked more than once and showed to be within service limits. In fact the report at the time was not even that loud.

Was the gun okay / checked by a knowledgeable person? Sounds like the gun may not have been completely in battery allowing the separation.

Was the gun okay / checked by a knowledgeable person? Sounds like the gun may not have been completely in battery allowing the separation.

Yes, it was checked out by several competent people and was in battery.

Had a similar incident years ago with CCI Blazer 45 ACP. Case separated at base of bullet. It was shot in a 1911. Back end of case ejected into mag well sending mag out of gun and breaking one of the grips off gun. Head with case still intact around it went down barrel and stuck at muzzle. Sent remaining back to CCI at their request. Got a letter back stating ammo not at fault was most likely gun. They sent a coupon for free box ammo. Used a cleaning rod and hammer to clear muzzle, put new grips on, miked barrel, and been shooting it ever since. Works fine. No problem with brass shells ever since that day. Threw away letter and coupon. Walked away from CCI Blazers and never returned. No injuries that day either.

 

I believe the aluminum case may have been misformed, or the case was damaged somehow during bullet seating. The barrel after this incident was checked more than once and showed to be within service limits. In fact the report at the time was not even that loud.

 

 

You may be on to something with the bullet seating. It appeared the case separated right at the heel of the bullet. The slight, extra bulge there may cause the less ductile aluminum to weaken in this area and cause the separation. Additionally, the hot gas hitting the base of the bullet and fanning out may be the final factor in causing the separation.

 

BTW – I doubt it was an out of battery problem. I was the RO and right next to him and nothing unusual occurred during the discharge. The only reason the separation was noticed was the upper section of the case went over the round coming off the magazine and caused a jam.