How critical is it to tighten and loosen three times when installing a new barrel to a new receiver?

Uhhh, i didnt!!!!!! I wasnt useing a brand new receiver so i just uninstalled the old barrel and stuck the new one in. Tightened it till it was hand tight, then stuck a torque wrench on it and went to 35 ft lbs.... hast let loose yet and works like a champ.........

Don't even sweat it.  I've built thousands without doing that and have never had one come back for that reason.

I was just wondering as I only tightened it twice and then concentrated on getting the gas tube lined up properly. But you know how it is with those damned nagging doubts. Should I or shouldn't I, or oh for Pete's sake don't worry about it.

All the "torque three times" thing is about is smoothing out the new threads so it will tighten up smoothly.

And the exact torque is not important, 30 is recommended minimum, but truthfully, 25 is enough.

If you get to 30, and the notch is lined up correctly, fine, stick in the gas tube, you are done.

If the notch is not lined up, remove the torque wrench, replace with a long breaker bar, and continue to tighten the nut until alignment is achieved.  The long breaker bar will give you finer control over this process.  

Alignment may happen at 30, it may be 50, or 75.  It will not automatically line up at a magic number.  No big deal.

It is not critical at all.

The only reason they do that is to make sure that it is fulling tightening on the receiver, and not getting tight because of some thread deformation.....

Just get it good and snug, then keep tightening up to the next gas tube hole alignment.

I dont even use a torque wrench.... my hands just know it by feel.