I have a 8mm barrel that I am real carefull on when and how I clean it. I have noticed recently that there is a spot about 2.5" from the muzzle, that seems to have a very heavy build up of copper. It kind of looks like an AR15 looks right at and past the hole for the gas block on the amount of fouling. It seems to get worse the more rounds that are put throught it. I have to foam it 3-4 times for it to go away. It almost acts like a tight spot right there. You can not feel it when cleanig though. This is chambered in 8x57 and it is a Shaw barrel. Does any one think that the Tubbs final finish might work to smooth out this area? I am not worried about the throat moving out too far as this thing has a very short lead. I have to seat the bullets under what all the books call for by .01". So has anyone had luck with this system?
The Tubbs system work realy well on factory barrels realy helps to smooth out and even out the bore. If your not worried about lengthing the throat a good bit then give it a shot but you WILl lengthing the throat.
Generaly what I do is shoot half of what the directions reccomend then shoot some regular bullets through it to see if it needs more. I personaly would rather sneek up on it that over shoot it (no pun intended).
It is a long and drawn out process especialy in the summer whan it takes forever to get the barrel cool.
Just take your time use the slowest evlocity you can find and make sure that you clean the barrel VERY well between shots.
BUT first I would recomend trying some JB Bore paste to clean with you can add a very little extra effort to the dirty spot. I have even heard of guys using jewelers rouge to smooth out tight spots, I woulden't recomend that but I know the JB works great
I have tried the JB. It does get the fouling out at that spot, but it comes back right away when I shoot it the next time. Oh, I typed the wrong # for the seating depth. It is .1" shorter than what the books call for.