i was a little hesitant to start another Hammer post. Well I guess I will give in and ordered a box of HH146 for a 7RM. I have 9.5 twist and website states 10 minimum. What I find perplexing is the HH143 recommends 9.25 or faster. I have been under the impression that heavier bullets usually require faster twists. So why would the 143 require a faster twist than the 146?