I have some once fire .308 brass that I have already resized and deprimed. I have not measured the brass (awaiting delivery of calipers) and my primers were delivered today. Would I be able to prime this resized brass then trim (if required following measurement), or am I better off waiting to trim the brass then prime? I have not gotten round to buying a manual yet. I will be getting one prior to loading any powder & bullets for sure. Thanks all.