I know that the carbine locking nut is 40 +-2 INCH pounds and I know that torque values are to be set in conjuction with the standard government wrench.  (I've never seen a govt car stock wrench - I assume it has a square hole for a torque wrench).

All of the carbine stock wrenches I've seen either have no square hole for a torque wrench at all (just used by hand), or there are LARGE differences in the location of the car stock area on the armorers wrench, depending on the maker.  Ex:  DPMSs new wrenches have the car stock area pretty close to the torque wrench hole - the Olympic Boss wrench I just bought has the CS area at the end of the "handle" of the wrench - far from the toque wrench hole, so there is no way in hell that those two wrenches can give accurate torque readings (unless one is configured like a govt car stock wrench).

What's the REAL DEAL on torqueing a car stock nut if you don't have a govt wrench in your hand.

I do know that 40 INCH pounds isn't much, and I can accept the answer "get it snug, dude" if that is in fact the answer.  It's just that 40 +-2 INCH pounds is a pretty damned specific torque value!!!

Thanks

Put a couple of drops of Locktite on it, both where it threads into the receiver (don't get excess in the buffer detent), and on the thread area where the nut will snug up...and snug it up firmly by hand.  And don't worry about it.

Thanks, AFM.

Agree with A Free Man.  However, make sure you use the blue (medium stength) loctite, not the red (full strength)or you'll play hell getting it off again.