I am in the process of loading up some ammo for my brand new RPR in 6.5 Creedmoor. I want to start out with a Sierra 140gn HPBT on some Starline brass. Brass has been sized and trimmed to length. I used a Dremel to put 2 vertical cuts in the neck of a piece of brass to let me place a bullet lightly in the neck and chamber it to get the overall length for my rifle. I would then knock off 0.015" to get the bullet off the lands. Only problem is ... I am getting numbers below the Sierra specified 2.81", even before backing the bullets off by 0.015". I am getting an average of 2.75 or so. I have been carefully closing the bolt on the loose bullet so it doesn't get jammed in too far by the force of closing. My calipers are good because they read the bullet diameter spot on. I talked with Ruger and they dont even want to talk handloads - they only recommend ammo manufactured to SAAMI specs. I understand the legal implications, but my concern is that the chamber is too tight and that even factory ammo may yield an overpressure condition. I dont think I should have to buy tooling to check this ... Anybody have a similar experience?