Yes, I have shot it on a non-threaded barrel. It seems that it wants a very high velocity round, although there is a learning curve, I've had better "bursts" using BPR 40 gr 1435fps than Thunderbolts at 1255 fps ammo. I equate this to a stronger blow back, I was thinking that the Enhancer would increase the recoil in the lesser rounds by directing the blast forward allowing the gun to re chamber easier.
Something else I was thinking was to trim a coil or two off the recoil spring on the bolt