03-07-2025, 12:05 AM
Thanks for the great info. I was breaking my head for a while there. I also had similar findings with 200 rounds of mixed Hornady Match and Black twice fired from my gas gun. My SD were all over. Once I segregated them by grain the SD greatly improved from 17-10 fps with 10 shot groups to 10 to 6 SD. I still noted some outlier ES with in them still and a lot of overlap between the 1 grain groups. I'm now trying to segregated them further into .5 grain groups and keep better track of the heavier vs lighter ones within to see if i note a difference or if it just noise from other factors I did find a high correlation between weight and volume, which I hear is not always the case with Lapua brass. I was able to get my hands on 100 peices of new Alpha brass which are all within 1.5 grains of each other. Haven't shot them yet but they're all primed already so don't want to fill them with water. I'm going to weigh and shoot them and really hoping to not find any correlation so I don't have to weigh them every time.