Re: tight stock
I had a model 77 in 308 with a laminated stock several years ago that I traded because it wouldn't always fire my reloads. When I first got it it shot terrible groups at 50 yards. I finally got it to shoot 1 inch groups at 100 yard. The stock had a pressure point on the barrel at the near front of the forearm. It didn't contact the barrel in any other place. I would remove the stock and take a look to see if it's binding any place. You could also refer to one of the Ruger forums that may have the answer to your problem.
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