Polishing the feed ramp is a really good idea. Also, mine had some really bad gunk down in the guts of the action that needed cleared out.

I was using Remington T-bolt (bad); Winchester Wildcat ( pretty good); and CCI stingers (very nice). Out of ~300 rounds mixing them all up, I had only 1 failure to fire but three failures to lock the slide back after the last round. That was fixed by the hard cleaning of the guts.The slide catch was hanging up and never bit all the way into the slide.

I love this thing and I am currently in the gubmint tax stamp thing for a Gemtech suppressor to throw on it. Should be a lot of fun but it looks like the gubmint will take their good, old time processing things.

Tony