Originally Posted By: roky0702Adjust the screw all the way closed then slowly open it up firing with 1 round in the mag each time until the bolt locks back on an empty mag
I would suggest starting with the gas block open, then closing it down until the rifle ejects but does not lock back. Then, open it one click and see if it will lock back. The problem with closing the gas block is that with each shot, you increase the chance of the case sticking in the chamber and needing to pogo the rifle to get it out.
You shouldn't need to start with the gas block wide full open. Set the gas block about half way open, depending on gas port diameter.
I have an SLR adjustable gas block on a suppressed shorty AR and it makes tuning a snap