Shot some test rounds today, 55 gr. Cast. Used re-7 at 15.6, 16.0 and 16.5. All loads cycled fine, but none of the loads would lock the bolt back on the last round. Is this kinda normal shooting cast in an ar? Its not a big deal if it locks back or not, just wondering. Not sure if I want to up the load anymore, lyman manual shows 15.7 as max load for that bullet. No leading at all. Thinking of loading more at 16.0 gr. And check accuracy.