Skip: I respect your opinion too, and you have a valid concern about wear over time. One only needs look at rocks in a river bed to illustrate this wear effect. All my custom barrels have what some would call a "custom crown". Meaning that the muzzle usually has either a "floorboard" crown, or a "dual crown".
With a dual crown, the muzzle has an 11 degree bevel to the edge of the barrel diameter for optimum gas escape on the base of the bullet, and the actual crown has a 60 degree/20 degree cut. The 60 degree cut is for the brush to re-enter the bore without damage, and 20 degree cut is to break the 60 right at the actual origin of the rifling.
This method of crowning allows the brush to re-enter without worry of damage, and after over 5,000 rounds from some of my custom varmint bench rifles, other than chasing the rifling with the bullet to maintain consistant contact with the lands, they all shoot about as well as they did when the barrels were new.
Darrell Holland first made me aware of this method of crowning, and now I employ it on every rifle I have made up, I've even had some factory barrels re-crowned this way.....seems to work very well and allows "normal" cleaning procedure without unscrewing the brush for every pass back down the barrel.
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