I'm trying to remove the barrel nut from a Prof. Ord. Carbon 15.  The barrel nut is not standard and Bushmaster doesn't offer a wrench.  So I made a wrench from a piece of flatbar and inserted two dowel pins (1/8").  My first pass I broke one of the dowel pins trying to loosen the nut.  No damage to the nut (thank goodness).  I've inserted shorter pins, but I'm afraid to whack the wrench because I don't want to damage the receiver or barrel.  Any experience or advice?

thanks
-yj

I have not tried to put my barrel back on yet, but I will be doing that soon (I asked that Bushmaster return the gun to me disassembled after completing some work on it). I spoke with the gunsmiths at Bushmaster and they said to use the same approach you are trying. You can try better materials or more pins and make sure your axis is the same on your tool and the nut. Good luck. And tell us how things are going.