I just used it on my XP-100's factory 7BR barrel. It shot accurately, but fouled rather easily, and took awhile to clean with jacketed bullets. I wanted to use cast bullets, but with the rough bore, wouldn't even try it. I used the last three grits (of the five) in the kit, and used them as directed in the instructions, and the bore is noticably smoother when running a tight fitting patch down the bore. It also seems to foul less, and is a snap to clean. I can't comment on any tiny accuracy increase or loss, as I don't shoot from a bench, the gun is shot using the Creedmore position for silhouettes. It seems just as accurate, and now I am using cast bullets @ 2050 fps in the pistol, something I wouldnt even try with the barrel before the treatment. I would definately recommend using FF on a gun that has a rough bore, especially if cast bullets are in your future.
