I use a torque wrench on the barrel nut to 30ft lbs. Then add what ever pressure to get to the next hole as required on some model of hand guards so the gas tube lines up. Lots of new hand guards now use a nut so the tube line up isn't relevant. In that case I torque to 60ft lbs. Max. ft lbs. listed with uppers and hand guards I've seen is 80 ft lbs. I've moved to this type barrel nut wrench so I can use my 1/2" drive torque wrench. I mount this in the vice then set the barrel muzzel facing the floor.
http://www.brownells.com/gunsmith-tools-...od468.aspx
Then insert this thru the upper and torque accordingly. Must be catching on, sold out.
http://www.brownells.com/gunsmith-tools-...=BROWNELLS
As for gas blocks, yup, no real spec that I have seen and stripping out a allen screw sucks, or breaking the tip of one off. Speaking from experience on that screw up. Since then, I use blue lock-tite and snug them up hand tight. When removing them, you need to use a heat gun and heat it up to free the lock-tite and then your good to go.
Comps or any muzzel device, again a little blue lock-tite then snug it down and and if using a crush washer, I don't use lock-tite.
Not sure on the buffer tube, again, I just tighten till I feel its good, that won't be dangerous as not having a tight barrel or muzzle device. Make sure they are secured properly.
http://www.brownells.com/gunsmith-tools-...od468.aspx
Then insert this thru the upper and torque accordingly. Must be catching on, sold out.
http://www.brownells.com/gunsmith-tools-...=BROWNELLS
As for gas blocks, yup, no real spec that I have seen and stripping out a allen screw sucks, or breaking the tip of one off. Speaking from experience on that screw up. Since then, I use blue lock-tite and snug them up hand tight. When removing them, you need to use a heat gun and heat it up to free the lock-tite and then your good to go.
Comps or any muzzel device, again a little blue lock-tite then snug it down and and if using a crush washer, I don't use lock-tite.
Not sure on the buffer tube, again, I just tighten till I feel its good, that won't be dangerous as not having a tight barrel or muzzle device. Make sure they are secured properly.