Go shoot one and find out. Just kidding. Im sure they make a big hole just like every other slug out there. My step dad got a doe with a 12ga barnes expander this year. It dropped the doe in her tracks and didnt tear up too much meat.
I have killed 14 deer in the last few years with the copper solids. I use a 12 gauge fired from a Marlin slugmaster. The copper solids are very deadly. All 14 deer were killed with one shot. Most were dropped in their tracks. All were recovered within 25 yards from where they were hit.
Shot three Copper Solids this year. Once to verify my scope was still on and one at each buck I killed (1 in a park hunt, 1 regular season). I have been very happy with their performance on deer. Shooting mine through an 870 with a fully rifled barrel.
I shot my first deer this year with one from an 870 with a rifled barrel. It was a 100 yard shot with iron sights as he was coming across a field. I hit him a little far back but he only ran maybe 50 yard to a tree line, bedded down and died. There was a very large hole.
They also sighted in from my gun the best. I tried SST as well.