I broke my autoloader in by patterning my Extrema with some (+/-6 shells) 3.5" turkeys loads (one or two of the first shots the hull didn't fully eject).

I then shot 4 rounds of skeet; the first two rounds (2 boxes) I shot with #7 1/2 high brass, the following 2 rounds I used Wal-Mart Federal 1oz #8's - never a problem.

Read your manual (break in procedure)..................you'll see !