Update: well, I was working on Darren's 10/22 receiver this morn checking the fit of the new synthetic buffer stake pin and found a crack in his receiver. I don't know how I missed this before but was working under artificial light and today had brite sun coming in. I had already drilled the rear of his receiver using the Brownell's Jig for this very job and didn't notice it then. Called Ruger and being the weekend didn't get very far with them but I think there won't be any help because of me drilling the rear of the receiver which they look on as a user modification. Got a employee at Clark Custom, though, and they think it can be repaired. Long story short I feel really responsible for this so offered to buy Darren a new receiver and of course he turned me down but I could tell he was really glad I made the offer. I have mixed feelings about allowing a repair to this type of problem and will prolly just get him a new receiver anyway which leads to the prob of the custom barrel from Lilja has an over size collar due to mine & Darrens measurements of the receiver opening for the barrel. Just another day in the life I guess. Will keep you all posted, thks.....