I think that you are right on the money with that, and I have put forth that idea for a long time as well. Think about it, if it was bullet SPEED that wore out a barrel, then the MUZZLE end of it would be worn down the fastest! As it is, the predominant theory and logical one at that is that the throat erosion is caused form unburned and burning powder being blown down the tube like flaming and mega hot sandpaper particles. That, along with hot gases acting as a cutting torch. From about 2 inches or so on down, we have only expanding gases working on the base of the bullet and for the most part negligible wear all the way to the muzzle even though the bullet might be reaching 4000 fps out there. If someone ever solves the puzzle of barrel wear at the throat with high intensity cartridges a lot of financial success will come their way, I would guess. Maybe Roy Weatherby had it right with freeboring those high velocity rifles so as to 'pre wear' the most affectd areas and not lose rifling or have it go gunnybag since there weren't any there to begin with.
Last edited by safariman; 12/08/11. Reason: SP
