400 should be heavy enough of arrow, but I would look at another broadhead. Just me. I am starting to put my faith into well made fixed blade heads. I have shot several deer with different mech heads that just plain fail to penetrate. Blood trials are always better with two holes.
Now that said I have harvested two does this year both with mech head. Shooting almost a 475 grain arrow. But now have swapped everything back to muzzy.
Good luck and let us know what works for you.
