I built a 22-250 Ai with one , it shot great cleaned up great. It was just an overall good barrel , I woulden't say it was any better than a Lilja , Hart or Kreiger that I've uesd as far as accuracy and fouling goes , it diden't realy give any more velocity than any other custom barrel.
I will say that it diden't wear as fast , I shot only 55gr moly coated V-max bullets and when I sold the gun it had better than 1200 rounds and still shot under the 1/2" mark , it originaly would shoot in the 1/4" range but oppened up after about 500 rounds then settled off at around .3"s and .4"s
I bought 6 of them when Brownells discontinued them I still have a 1-12 twist .257 that 30" that I plan to built a hot rod with one day.
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