Not for MILSIG M17 SMG

Twice installed the kit on my MILSIG M17 SMG, the first time the bore sizer housing bent at the internal portion as I think the hammer struck it, needed to use pliers to get it out and scratched it all up. The second time, the hammer actually wedged in the .679 sleeve, works good in my BT4, my son has a kit and worked well in his BT4.

Super Useful Kit

Considering how inconsistent various brands of paint has been, even within the same brand the paint sizes change, so having this kit has been helpful to match the bore to the paintball. Now no matter where I play, it does not matter what paint they offer. I recommend this as it will improve accuracy and help get more breaks on the other team!

Works well only complaint is the thin/weakness of the metal.

I really like this product my only issue was when I went to unscrew it the one time just the barrel came off and not the bore sizer kit so I had to take channel locks to the kit to get it to unscrew because it was on so tight. The bore sizer kit got bent a bit because it is such thin metal but I manage to fix it and it still works fine. It is just a little tight screwing on barrels now