The break and tune kit work great except for the poly tube. It was too long when I first put it on, so it was crushed when I put the rifle back together. With the next tube I tried making it little smaller so when the rifle gets put back together it doesn't get crushed, didn't cut exactly straight all the way around and so that one leaked too. I'm back to the original orange colored one, which is fine. Just wish I could have got it right see the difference in performance. But overall the break and tune kit is a great buy. Pellets hit harder even just with the different bolt.