Re: 6-284 ?
Ok screech now I understand. 6-284 with a 87gr V-max 3700fps+ or you can go with a 80gr Berger 3800fps+. Another combo would be a 70gr B-tip around 4000fps. If you choose the 55gr like you asked look to use Varget, R-19 or IMR-4350. If you go with a slower powder then those you will not get the speed. By the way I have shot those 55gr B-tips out of mine with a 9 twist and they were pushing 3950fps with 56gr of R-22 and they held together fine and shot very well. But a faster powder will give you a lot more velocity. R-22 was just to slow for that light of bullet because I was shooting 80gr bergers over 3800fps with it so I know for a fact mid 4's should be easy with a bullet 25gr lighter with a faster powder.
Fast, Flat, and Accurate