Hey Roger, Yes #51 or there abouts. Another thing about the breech I showed in my pic,,, just my personal opinion but it took me about 2seconds when I first saw it to decide that its rebushed. Not because it isn't greatly enlarged or anything, it just looks like there is a bushing in there to me. Not something I've ever heard anyone else mention, and I sure don't want anyone to think I'm trying to degrade the gun in any way, or if that even would... just my opinion. Regards, TC