It would seem that you are using a bullet too light to perform well on paper at 600 and even worse at a 1,000 {falling out of subsonic and wind}.Guess I should have mentioned, I will do target paper and gong shooting only, 600 and 1,000 yards, so terminal performance is not a consideration.
THIS,.. ^^^^It would seem that you are using a bullet too light to perform well on paper at 600 and even worse at a 1,000 {falling out of subsonic and wind}.
You have not mention cartridge but unless you are shooting some sort of pistol than I would suggest that you consider bullet weight in at least 165gr category.
Yeah, start it at 3400 atleast it will be supersonic….but whyI have a hard time imagining a bullet launched from a 7 PRC not remaining supersonic to 1,000 yards.