I shoot a 26" '06, which gets me fairly close to a .300 with a 24" barrel.
Anyhow, I did a comparison at 500 yards on a steel plate, with Sierra bullets. GameKings. 150-grain SPBT, 165-grain HPBT, and 180-grain SPBT.
All grouped just inside one MOA. The 150-grain made a slight dimple in the steel. The 165-grain made the beginnings of a crater, but very little splashback of steel. The 180-grain definitely started a crater, with some splashback of steel.
I've killed deer with both the 150- and 165-grain bullets. There was an exit wound for the majority of all hits.
While I've not used the 180-grain bullet on deer, my opinion from what I saw on the steel plate is that it would penetrate quite well on a heavier animal such as an elk.
FWIW, Art