If I was him he should really buy some extra inserts. The whole point like jOObacca said is to match the paint to the bore size. Buy two more inserts, one smaller and one larger. That will help him match it up more precise. Think about it having a freak and having to match the PAINT to the BORE is just wrong. Have him do himself a great favor. He has a great barrel so make it even better and buy a few more inserts!
When you wipe, I only shoot faster...
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