I run a straight-from-the-factory Barrett 98B with a 20" barrel. I reload lapua brass with lapua 300 grain HP and 85 grains of vihtavuori. I can't remember if I figured 2400 fps or 2500. Ill get back to you on that. I'm also down in south Florida where the temp is the same as the humidity (90ish) and the elevation is lower than your shoe size. You guys are super helpful btw.