Today I'm loading some 9mm. The brass is mixed head stamps. I noticed that when I was expanding the shells for the projectile a few like (4) didn't seem to expand. They were already that size or bigger. I put those aside just so I didn't lose them. Then when I went to crimp those same shells crimped but the bullet lose. I was able to push them in. So I pulled them back out to length and crimped them more to the point it were it looked like half the shell was crimped. The bullet was still able to be pushed down rather easy. Needless to say I didn't keep those rounds for storage gunna recycle. But after all the crimping done and didn't hold the bullet, is that a sign of a over used shell? It went through the resize, Decapping die. Why was it so big? Anyone know?