Not necessarily "Shoot SAAMI Factory loads." Most custom chambers are tight and in a many, custom barrels, the necks have tobe turned to properly fit the chamber , "Case Body sized to specs, Not SAAMI" Also". In other words, No slop, such as we fined in our factory barrels. I almost wanted to ask the question earlier in the post if he tried trimming his brass down a few thou to see if that could be causing the pressure issue. Custom barrels are only as good as the machinist on duty that day. A 100% perfect custom barrel will only preform as well as the Person that installed it, also. I've seen quite a few cases where people have ordered a custom barrel and put it on a stock Rem 700 action and for the life of them could not figure out why it shot like crap. Also I'll say this, I hope it helps some what. My custom rifle is in the beginning stages, I promise you this. I will not be using a Christensen any thing. May be they will see this and turn their nose also. Good luck with this Sir, I truly hate it for you.