Competitive benchrest shooters look at a quality match winning barrels and their care a differently than a lot of us do,, it's much more than a tool to them and more than just a rifle barrel, when they get their hands on a match-winning one hole capable barrel they will do anything to keep it exactly in that competitive winning condition, something to be learned from that ,it just makes sense as that throat begins to erode and you're cleaning your barrel after every 20 or 30 shots , I would think any kind of brush, I don't care if it is a softer metal like bronze it's also going to affect that throat erosion, I can see a lot of you smiling or laughing at that, but again a lot of you aren't trying to put bullets in the same hole either. Now I guess us muzzleloaders since we don't have a bullet chamber and a throat in the gun it's not such a concern but maybe what I can learn from this for me is learning to get my muzzleloader barrel it's clean as I can in as gentle a manner as I can. I have come to believe this most of us don't know how to truly clean our muzzleloader barrels , maybe I'm wrong it's just that the four used muzzleloaders that I've purchased that had quote perfect bores and we're in excellent condition on the outside all had some serious serious bore issues when you truly got the light on and looked at them. Most of my shooting passed has been in bench rest it's hard for me not to approach any of the muzzleloaders I have and that I've been shooting the last seven or eight years and not see them as benchrest rifles I struggle with that,,, but I'm going to stay in that camp and that's why I'm always accuracy above bullet performance and it's why I won't keep a rifle if it won't shoot a half inch or less I'm talking muzzleloaders, and I sure won't have a smokeless rifle if it won't shoot a hole ,I see a lot of guys that are content to shoot an inch and a half or two inch or even 3 inch rifle I couldn't do it. To me an inch and a half rifles fixing to get sold or rebuilt especially in today's world 50 years ago I'm sure that would have been acceptable but there's no way I would accept anything less today. Thank you encore for that link!