Yorke,
When you say erratic, did you do measurements?
When you say they foul up pretty bad, what round count are you referring to? Carbon, copper or both?
Thanks
Yes, measurements. I've seen both oversized and undersized bores as well as incorrect twists.
The fouling is similar to a factory barrel where they shoot well when fouled, but they're incredibly hard to get clean of both carbon and copper. Most of the guys I know using them just don't clean them that often so it's not an issue.