I was looking at that gun again, Randy, and when you close the locking lever, the lever cams back against the receiver about .015" or so. There is a ramp under the lever on the barrel stub block, or a ramp on the lever that cams the lever tight to the receiver, when you close it. Or a ramp on both the closing lever and the barrel stub. I didn't try to take it apart, but that screw retains the lever, with a shoulder under the screw head.