I've been trying to shoot these 180gr plus bullets out of my 300blk with a 1/7 twist, 11.5 inch barrel, at what I think should be around 1300fps to 1400fps min load was 13.4gr Lil gun max was 15gr Lil gun. These bullets are a gas check design, however I ran them powder coated with no gas check. The mold I used was Ideal mold 309329 sized to 309. Most of the bullets did not hit paper at 50yrds, the ones that did flew sideways. Any ideas on what the problem might be?