Had an interesting thing happen while at the range. I loaded some cast .113 grain plinkers with 7.5 grains of Unique in a .30/30 Savage 325A. After about 20 shots I started to get misfires. I had loaded all identical to one another. I looked at the primers and the misfires where only lightly dented verses a heavy dent for the ones that fired. Could it just be as simple as dirty? Firing pin, spring? Anybody have this happen to them? Thanks.