I too have found 400 grain arrows at 275 will penetrate about as good as you would hope for. Especially with a COC head.

They don't work as well on male hogs with chisel points but they do poke through the exit side most of the time with COC heads

When I shoot 450-470 grain arrows at 230 fps the poke out just about every time on big hogs

On deer bears and elk the 400 grain arrows are good. I hunt with a guy that shoots 480 grain 30" at 290fps. They are massively powerful. He has used these for years. However this year he gun hunted only. He is having some shoulder problem now.

He said "I may have to make some changes in my archery gear, that 75lb draw might be unattainable after my shoulder heals. "

I'm not a fan of FPE measure for killing power. There is a connection though. I would not shoot a 2" expandable under 70fpe

And I think 60fpe is a very solid big game power level.

Below 50-55fpe folks need to be careful in distance and species choices.

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