My Dad killed a lot of game back in the '60s. Rem 760 in 30-06. 150s for deer, 180s for elk, W-W Silvertips for all hunting. They were really special...made with actual silver alloy.
I was about ten years old and tagged along as Dad attempted to track a double lunged cow elk in dry dusty conditions. The foaming blood trail eventually stopped and we never did find the cow.
I suspect due to inadequate expansion.
But Dad swore by the bullets and would never use anything else. He has not been to the hills in a couple decades, but was telling me recently that the Silvertip was the only thing to use on game. He was sorely disappointed when I told him they had been discontinued long ago.
He never has believed me when I tried to explain that it was just another lead core bullet with a shiny coating over the tip.