This is on a Coldsteel RPK receiver. I started out intending to do a screw build, but the poor fit of the rear tang on the rear of the receiver required welding. So I switched it to a weld build. I have 2 of these receivers and they both fit the front trunnion in a beautiful way. The snug right up to the raised area and required little fitting. But, the rear block is narrower than the normal 1.25" (like 1.20" or less), plus the receiver is little wider inside than 1.25" (like 1.30 or more) creating a visiable gap all around the rear block. A tiny gap could be ignored perhaps, but this one looked bad when it was squeezed down and the sides pulled in at the top but wider at the bottom. I could not live with it, so I welded the rear block around the entire back to make it look seamless and then spot-welded the sides as well where the rivets would normally be.
Will test it this weeked, but first it needs a good electronic bore cleaning
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