I have 467 rounds down the tube of my 6.5x284. The throat has moved a bit over .03" since round #1. If I'm lucky I'll get 1400 rounds before I make this tube into a 22" hunting rifle barrel.
I scrub the crap out of it, with a copper brush, after each match. If I didn't, it would have so much copper it I doubt it would shoot. 308win, you're not likely to have the same kind of copper fouling issues as a hot 6.5x284.
If I could clean my bore by pushing patches though on a push style jag I would, but that's just not an option.
I do not use a Krieger on this rifle,and my caliber is different, so your results will obviously vary but I'd use the brush sparingly and not let it exit the crown. I assume you've read Kriegers cleaning recommnedations http://www.kriegerbarrels.com/break_..._cleaning.html
. I can't see a copper brush causing wear and damage to the crown, so long as you don't allow the rod to slide on the botton, much like the throat.
If Krieger believes JB's abrasive cleaner is fine for the barrel, a brush should be alright,,, and when you recrown, you only need to remove about .025" worth of material around the muzzle. Just enought to clean it up. Brownells sells kits to do it yourself,, and I've heard of some brave souls (NOT ME!!!) doing it with a stone tip on a dremel. It would depend on how far back in the bore the damage exsists.
[ 10-10-2002: Message edited by: FatBoy... ]