I had a 54 cal perc. GM heli-barrel. They installed the insert too deeply into the flash channel and had MANY MANY mis-fires.......(do a search here, ca. Nov. 2005)
I wasted ca. 1 lb of powder and a bunch of lead until I unscrewed the cleanout and saw the threads hanging down where they should not be. :shake: I was cursing the caps I was using for no good reason til I found the source of the problem.
IMHO send it back, and tell TOTW you don't want a heli-barrel. Maybe if (all) the vendors who sell GM barrels start sending them back GM will finally do the right thing, e.g. RECALL THEM ALL!!!!
BTW, when I contacted GM about this they said this was their current way to make barrels, it was "stronger"and "ALL NEW BARRELS WOULD HAVE THE HELI-COIL".
As I see the latest GM barrels do not have this "stronger" feature I can only assume I was fed a line of B.S. :bull: :youcrazy: :shake:
P.S. Do not accept a B.S. story from them (TOTW or GM), if they won't get you a non-heli-barrel refuse it and get a proper one from one of the vendors listed above.