Shotgun sidesaddle induced failure

[Ed]

While taking the ITC shotgun class my pump 12ga mossy 590 would not cycle after 70-80 rds of buck, skeet and slugs. The problem was created with a side saddle that I had over tightened - as the shotgun got hot due to firing and being in the heat the receiver warped slightly and the side saddle caused it to bind. Moral of the story- dont over tighten your side saddle and use a small dab of locking glue.