Is there a reason Custom builds Do not Ream Chambers to fit, Then ream Free bore to fit the customers request? This would seem like an easy enough process. Fit the brass to the rifle, bolt, feed, etc. Next The simple ream of bullet dimension, no harder to keep strait than using a guided cleaning rod. Free Bore could easily be done after barrel was installed and Customers test [Dummy] cartridge was used. {Input welcome if I missed a fine point, I do home shop machining pretty well} (First to admit we all have room to learn) Thank you for your time.