Issues with psa gf3 retention - FAB Defense AK/AKM Picatinny Scope-Mount Dust Cover

I was able to get this rail mounted onto the rifle and tightened down as tight as possible using both hands and material to avoid losing grip while tightening. The lock up was very stiff. I did however notice the rail was not set tight up against the rear sight block. The spring loaded front clip on the rail was connected to the lip of the rear sight block, as designed, but it was about halfway on leaving a small gap. I know the rail was installed as far forward as possible because the safety lever, factory stock from Palmetto btw, was already being slightly pushed down from the top rail. I installed this rail carefully several times to ensure something just wasnt misaligned. Though this issue was never resolved, I was still able to tighten down the ratchet mechanism making it very solid. I was willing to accept the gap issue and the safety lever being lightly pushed down due to the aesthetic and functionality this rail offered. I mounted up my LVPO and set it up for storage. I was being clumsy and accidentally, but fortunately for me, knocked over the rifle and the rail popped loose. The failure point was at the small spring loaded clip at the front of the rail. The rear lockdown was still very tight and locked on. Out of curiosity I attempted to recreate the issue and took the rail back off and set it back up correctly with tightening everything down. I then smacked the front of the optic rearward and the rail popped back off the same was it had when it had fallen over and hit the ground. There are two potential problems. Either the Fab Defense rail is not in spec and was milled too small or my AKM rear sight block is slightly set forward and not in the correct position. I am leaning toward an out of spec rear sight block positioning from Palmetto. I believe this because my factory dust cover is also not fully up against the rear sight block and has a small gap as well. I believe I am just unlucky, however consider this if you are looking to purchase one for your PSA GF3. I would also suggest to anyone reading this with a different AKM manufacturer to perform the same blunt force test against your optic rearward to ensure the front clip will not fail on your rifle. Better to find out at home then in a moment when you really need it...
After writing the above, I wanted to be 100% before posting a review. I added the rail back on and took the good ol hammer (a soft deadblow one) to it. I was able to force the rail to close the small gap between it and the rear sight block. Success right? Not quite. I then tightened the rail back down and hand cycled the action a few times to see if anything moved. Unfortunately the rail started to move backwards and recreate the gap that I just closed. It appeared to me this may be an issue of not tightening the rail enough. I then took some channel locks to the rachet and got a number more clicks than I was able to by hand. Then experimented with hand cycling again to see if any movement arose. The rail did not move, however now the bolt was getting stuck when fully pulled back. I figured id deal with that after I see if this rail will be stationary. I added the optic back on and was not able to knock it off by hand, but a few light taps with the dead blow (to simulate a decent drop test)and it popped back off again. After taking the rail back off I was not able to see any wear spots that would have caused the bolt to catch in the rear position. No clue why that was ever occurring. I think I have given this rail every chance I can to get it to work on my specific rifle without causing permanent change. Again, I dont think this is a fab defense issue, but more of a rear sight block position, or perhaps even the receiver is just slightly too long. Regardless, hopefully this review helped those in considering the purchase.