I came real clost to doing the "full" bolt modification - the cutoff and insertion of a drill bit piece, but after looking at the bolt-end closely, changed my mind. The horizontal port had been drilled past the side-port opening, much too close to the o-ring seat - to close for my comfort anyways. I read in some posts of the end breaking off at the o-ring seat and did not want to tempt fate - not having a box of spares to experiment with. So I concentrated on opening the side and end ports to the same diameter and using lots of honing paste, rounded and polished all surfaces. I was also concerned that the small drill end may not exactly help direct all pellets into the chamber perfectly (pellets having internal differences among manufacturers) whereas the bolt face supports them all. In the end, it's all about having fun in the speculation and in the I may just have to buy another just to go through it all again - that's the definition of a hobby for me. When I compare the results (the fun factor), the investment costs are really minimal.