I just wanted to share my PSA barrel nut experience, because of how elated I am that I was able to get the barrel nut off my upper.  I got a brand new PSA 300BLK upper, but could not, as many know, find a 1/7 twist one.  So I bought a 300BLK PSA upper with the intention of changing the barrel out.


First pathetic attempt using an adjustable wrench

Next, tried with crow foot and breaker bar. cranked the crap out of it.  no go.

I got a 1 1/8" crow foot from summit racing. Luckily they have one of their major stores where I live.  That, and my breaker bar(noticed it got some bend to it while cranking on the nut).

Next, heated the shit out of it with a heat gun while using breaker bar/crow foot.  With moderate cranking, bingo, came loose.  removed the rubber piece because the wrench wouldn't fit with the rubber in there. and I'm loosening a part of a gun, not fine china.  Either way, it didn't mar at all.

PSA barrel vs longer BA Modern series 8" barrel

The amazing crowfoot in all it's shimmering glory that made this happen.


It helps to have basic car tools already like the torque wrench and breaker bar.

One thing I learned from this, from what I read, some PSA barrel nuts, the portion that is flattened for a wrench in some was sandwiched by curved barrel nut, causing people to have to grind it thinner.  I didn't have to do that, as any wrench overhang was large than the rounded nut to the side. Hope this finding helps someone down the road.  I really didn't want to have to grind down the wrench, only for it to not work and be unable to get the nut off.

The magpul bev block took a little bit of a beating but it's ok.  I was wondering if either the desk I use with the vise, vise, upper, bev block....any of that was going to fail while cranking on it.  I imagine you can't do this too much to an upper before you destroy it.  Glad this is a one time thing for this upper.  I feel like if I did this much torque on it several times, it's just asking for failure.  I torqued it down to a safe 40 ft-lb.

Put the whole upper in the freezer for an hour or two and then try again with the wrench. My last one that was amazingly tight came right off after some time in the cooler.

edit - misread, I thought you still had it stuck. So, see above for next time I guess.

I've never had trouble removing psa barrel nuts and I've removed several. Granted, I have a combination wrench the correct size and use a vise with upper jig.

Most stubborn one I've ever had to remove was a delta nut on a Colt match target rifle. That thing was a bugger and I had all the correct tools.