Originally Posted by CPGfan
Gotcha. I have found in my 6.5-06AI's a 215 will make about 50-75fps difference in velocity with the same powder charge. Although I do have one now that shoots better w a 210. Shooter preference for sure, I will typically run 215's in everything from my 243AI and up. Lookin forward to hearing more progress on your build. Looks like so far so good!!
The reason you get that much velocity increase is because you are increasing pressure with the hot primer. Sometimes you can load a heavier charge with a std. primer and get better accuracy with the same velocity.
With H1000, I even load std. primers in my 30/375 S.I. with 80+ grains of powder......Rich