I have never on semi inlet stocks had one that you could slip on your frame without altering it to fit. Once i was using a Show Me Fox semi inlet stock and when i got top tang close to going in all the way there was a noticable gap. I carefully examined the sides of the tang and found there must have been a defect on one side and factory had filed it out. I used that blank on another Fox and it worked out perfectly. Had to make a stock by hand for that frame. Bobby