I just finished my first AR last week. Just wanted to know if anyone has issues with barrel nut torque specs not quite hitting 30 ft lbs on the first notch and hitting 80 well before the next one lines up? Did I get unlucky or is this sort of routine? I used white lithium grease on the threads and a super grade of EP high moly content between the nut and barrel flange so as to eliminate rotational force against the index pin and the upper.
I ended up solving my problem with a lathe but most folks don't have a lathe. i shaved off .0028 which is more than I wanted but it took that to clean up the face of the upper which was out just that much. Upon trying to retorque I ended up with the same problem.... Duh that's the thread pitch per 1/20th of a turn, back to the lathe for another .0015. I ended up lining up for the gas tube at 70 ft lbs so I'm pretty happy, although a little disappointed that things were a little out of square.
I ended up solving my problem with a lathe but most folks don't have a lathe. i shaved off .0028 which is more than I wanted but it took that to clean up the face of the upper which was out just that much. Upon trying to retorque I ended up with the same problem.... Duh that's the thread pitch per 1/20th of a turn, back to the lathe for another .0015. I ended up lining up for the gas tube at 70 ft lbs so I'm pretty happy, although a little disappointed that things were a little out of square.