ahighercaliberco

if you replace the drop-in handguards with a free floating handguard then you did away with the drop-in handguard keeper. You will have to back-off the gas block .30mm from the barrel edge to get a good alignment of the gas ports. If your barrel was drill for retaining pins to hold on the front post sight check to see if the set screws on the gas block are not aligning in the groves keeping the gas block from being aligned. Check to see if your gas block is drilled straight thru for the gas tube, I had one that leaked from the front of the gas block.