I'm at 499 grains. I get 260 fps with these heavy arrows. That's plenty fast since a long shot for me is 25 yards. Penetration is not a problem. I've never not had a passthrough. And my bow seems to shoot quieter with the heavier arrows. I shot 373 grain arrows out of the same bow and you could hear the difference. Definitely a little louder. I could shoot 295 with these light arrows, but I like a quieter 260 with a ton of momentum better. And it's easier to group fixed blade broadheads at 260 vs 295 fps.