For a long time I have been using 1075 plus RWS caps and the .50 cal. Investarms Hawken has been very accurate and consistent shooting off of the bench at 50 yds. Today I went out used the same load, patches, and patch lube and had flyers both above and below (about 8") POA with the only difference being I used CCI #11 caps. Could the caps cause this? Hard to believe they would make that much difference. I've used CCI before and never seemed to have a problem.
