Re: Bullet speed for the mushroom?
I use well constructed bullets that both expand and penetrate. While I use Barnes X and TSX bullets the majority of bullets that I use on Whitetails are Hornady SP Interlocks. Except when using light for caliber bullets (like 130gr in 30-06/.308) I have never recovered a bullet in a deer. I shoot(all Hornady) 150gr Bullets in the .308 win and 30-06, 165 gr in the .300Wby mag, 130gr in the .270 and .270WSM and 139gr in the 7mm Mag and have never recovered one in a deer. I don't plan on shots and have taken deer from point blank out to 400yds.
Now I have found Nosler ballistic tips, Nosler solid base, Sierra GK's, Hornadt SSt, and Rem. CoreLoks inside of deer. While very dead, I did not like finding those bullets, especially on broadside shots. Sometimes some exited, sometimes parts of some exited and sometimes they were found mushroomed or in pieces. If I had to hunt with one bullet for the rest of my life it would be a Hornady Sp Interlock for every caliber I own.
Our forefathers didn't bury their guns. They buried those that tried to take them.