yes, it will help eliminate blow back. the two o-rings around the air inlet is what really helps with the blowback problem. also the material that is used is really good, the diameter of the bolt is just the slightest bit bigger then some of the other after market bolts, so with it being bigger it helps seal the chamber even more. the z-4 bolt is also so smooth that with the thicker bolt it does not stick and it is a self lubericating bolt as well. i had one on my BKO and now its on my B2K4/PDS.