Originally Posted By TW56:
The pivot pin hole is worn to where I can slop the upper back and forth.
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So in the
pivot shims thread, we discovered a excellent combo for eliminating play/slop.
The Pivot Shims eliminate side to side (3-9 o'clock) play. The Wheel Diamond Shim eliminates up-down (6-12 o'clock) play, as well as rotational wobble (twisting the handguard causing the upper to rotate slight counter clockwise).
However, when you say upper 'back and forth,' are you describing one of the above (3-9; 6-12; rotational) directions?
Or is it that the upper is moving forward and backward, ie that the upper can slide a bit toward the muzzle / back toward the stock?