Originally Posted by avfc1982
How are you finding it? Any zero shift?
The reason being that if you look at where the U section rail fits onto the front of the receiver it is fixed on one side with a countersink bolt and a single pin.
This rail needs to bolted both
sides to hold that rail securely. Before I did this, the clamp used to bear against one side of the reservoir causing poi shift when I filed up.
Now, the clamp sits evenly around the reservoir without touching and I don't have any shift.
I did originally try with no clamp, but found that as I wanted to keep the original muzzle brake, the barrel would 'bounce' giving me odd random fliers.
Once the clamp went back on with the just the O ring gripping the barrel, the fliers stopped, so result.