Should a new 20 gauge Mossberg semi need to be broken in before it ejects 7/8 ounce factory loads? A guy I shot with today has a Mossberg that readily cycles 1 ounce loads, but frequently chokes on 7/8 ouncers. This is after breaking it in on 200 1 ounce loads. He says he cleaned all the grease and preservatives out of the gun before shooting it.