35# ?

Spec is between 30# to 80#.  On a standard mil-spec nut, you torque to 30# and back off three times, and then tighten until the gas tube notch lines up...without going over 80#.  
If it's juuuust past lining up at 30, you'll likely have to over-torque to get to the next notch.  In that case, a shim might be required.    

On many of the barrel nuts used with handguards today, there aren't any gas tube notches.  
In that case, I typically go off the recommended specs from the manufacturer (if provided) or just set torque wrench to 45# and call it good.  
Same thing, torque to 45# three times and back off, then do a final tighten.  This seasons the threads on the receiver.  

Thanks RJ

Put some lubricant on the threads.  I use aeroshell but others use other types.

Just got my centurion 762 rail, in instructions

Torque to 30# then back off

Torque to 45# then back off

Final torque of 60#

No gas tube lining up with this barrel nut