"GreenO, are you saying you tightened the barrel nut or the retaining cap? My barrel nut is VERY tight. I had the choice of just a hair past hand tight and REAL tight to line up the gas tube after my 3 tighten/untighten series and went for the next hole. My retaining cap is just average tight. "
The FF handguard retainer cap/ring whatever, I always have the same choice- barely tighten the barrel nut or tighten the piss out of it, So I always torque my barrel nuts to about(my guess) 60ft lbs or more, as I am not comfortable with the next looser notch..
My strap wrench is just one of those stupid POS rubber strap and steel handle things, brand new it was $12.95, it is the smallest one I could find (the only one that woud work) at Walmart and Ace Hardware, I didn't want to drive to Sears or Snap on They are in Milwaukee. The point- It will only torque to about 30ft lbs before the rubber strap starts slipping. At this point it is very firm but there still is a little flex if you check it. I'm OK with it, I might at most put an IR laser on it. No optics are going out there so it shouldn't be a problem.