I hope you have better luck in you AI with the 33xc then I did. Things were great 1st time thru the brass no issues. I annealed sized trimmed and then loaded up my rounds and went to the range. To my shock massive pressure issues and blowen out primers. I tried H-50BMG, RL-50 and 24N41 and it didn't matter. Turned out to be bad steel. The steel in the barrel look like 500-600 rounds hand been fire when I had only shot 122. The barrel company stood behind and offer to replace but I had had enough of 33xc and had the send me a .308 barrel which still shoots great. I have talked to a couple of other guys on the hide that had pressure issues.
I would like to hear how your progress is going with it.