I HAVE AN ADAMS ARMS 545X39 UPPER.
Ima shooting surplus laquer ammo: the blot goes to the rear
far enough to cock the weapon, but not enough to pick up a round.
I have tried all the gas settings .
I did add the power hammer spring supplied with the kit.
Its a tack driver, you have to manualy put a round in the chamber useing the chargeing handle.
Any help would be great.
thanks in advance.
What buffer are you using? As long as you’re not using a Carbine buffer you can step down as many sizes as it takes to get the gun to run reliably. I take it its a complete Adam Arms upper, built by them? If so and the gun wont run with lighter buffers send it back.
Gas setting should be in the vertical position for normal fire.
I HAVE A CAR BUFFER TUB ,SPRING AND BUFFER
YES, THE UPPER CAME COMPLETE. VERY WELL MADE
IAM ALSO WAITING FOR A REPLY FROM ADAMS ARMS.
I BOUGHT IT FROM ONE OF THEIR SUPPLIERS.
Contact the manufacturer.
If you installed the system yourself,or have removed/disassembled part/all of the upper, you may want to make sure the gas block is CENTERED over the gas port. I use a 1/16" or the 0.050" allen wrench as a feeler to ensure that the gas port is not partly occluded in all my installs. you could also try a very small mirror ( plastic/toy ) cut down to fit inside the Gas Plus Assy hole in the gas block to visualize the port is clear and centered.
Also, ensure the Drive Rod slides freely through/past the barrel nut & the bushing you installed in the Upper Receiver. The drive rod should glide through the bushing with almost zero drag.
Hope that helps…
Ty Hoeffer
Palmyra, VA
I talked to John the Tec at Adams Arms to day.
Great Guy. I came home today changed the buffer spring to the shorter one , Added a lighter buffer. Its fixed God its great.
and clean up 5 min.
I all so tried my .556 p-mags they work too!!!
Its been a good day.
Thanks for your guys help.
Iam sure Ill be changeing a coulpe of my ars over to piston guns 
For that GREAT reliability??:sarcastic:
YEP AND EASY CLEANING TOO