I am not a pistol guy. Bought an HK 9mm yesterday for protection purposes. Bought 20 rounds of good ammo to keep and 100 rounds of terrible aluminum case ammo for practice. One of the primers blew completely out on the cheap ammo. There were no signs this had happened other than the gun jammed the next round. No apparent damage to the gun. Is this common in pistols? Have never had this happen (thankfully) in a rifle.