RE: Mossberg 590 help
I really don't know if they will interchange, but I would guess not. My reasoning is the 590 has a 9 round magazine which, being longer than the 6 or 8 round magazines on the 500 would make the span between the takedown lug and the receiver too short on the 500 barrels. If you want to know for sure, call Mossberg at (203) 230-5300 and talk to customer service. They should be able to help you.