Why when I chamber a round is my 15A dinging rounds? I hit the bolt release to chamber a round because I thought I was doing something wrong with the charging handle but still it dings the round. Rounds ejected by firing show only small scratches if any. Thanks for any help.
Which dings are the top, and which are bottom of the round??
Have you tried a different mag??
KyAKGuy
Don’t know if dings are on top or bottom and its with three USGI and four PMAGs. 460 total in this rifle.
A friend of mine who’s a police officer has your rifle and has the same problem. It doesn’t affect feeding at all, it just dings the casings. About 1000 rds through his gun so far. 
Those marks appear to be from the bolt lugs contacting the top round in a magazine.
Things look to be a bit closely fit. I’d discuss this with S&W.
I sent email with pics to S&W two days ago with no response yet. I will call tomorrow. If it was the bolt I don’t see why it’s only the first round I load that sometimes gets the dents. Most times it’s just scratches. I can tell by the sound when I drop the bolt when it’s denting the round.