https://www.youtube.com/watch?v=7aTLMiWskOs&t=30s
above is the bore from my JCG build with criterion barrel that I shot in matches last year
this is after a nice deep clean....it was not to bad
and below is a the LMR I took off the rifle that I installed the criterion on. I wanted this LMR to shoot but it just never did. Best I could muster even with reloads was tad under 5 moa...
https://www.youtube.com/watch?v=-84FWEiU8Ho