Disassemble the sling. Slide the J clip on the strap and through one half of the H buckle. Now slide on the Lock with the tab facing down, loop the strap through the D-Ring near the muzzle and back through the Lock. In use, create a loop using the sliding H buckle. Place that on the arm. Adjust for length with the Lock.
The M1 is a handfull in rapid fire. A tight position and tight sling will help control shot recovery. It will not change the POI.
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