You might be over-tightening your rear action screw. Pillar bedding could prevent that in the future. To convert to a blind magazine, you just need to find a stock for a centerfeed action that's inletted for a blind magazine. You can then remove the bottom from your detachable magazine by squeezing the two sides together, and install the magazine box and follower into your new stock. The magazine is retained into the stock by a small L-bracket, that you'll have to buy, the part number for it is 106135 and is available from Savage.
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