Just for some context, I found this small caliber bullet in the shoulder of the cow elk I shot this winter. You can see it’s fully flattened out and it’s jacket was nowhere to be found. There was no evidence that it ever hit any bone, either. I put my calipers on the nub of a base and would guess it was 22-24 caliber at one time. I presume that the elk would have likely survived and healed up just fine. The other bullet is a 225 Sierra Prohunter I used in my deer/elk rifle chambered in 338 win mag to kill the elk. In terms of appropriate dual purpose cartridges, folks have offered some excellent recommendations. They all work with the right bullet but I’ve found often that with elk a bigger bullet is more likely to be “righter”.
But, big and slow kills with less meat damage in my experience. Only elk I ever killed was with a 7mm Rem Mag. I used a Nosler Partition on it and it worked well at 200 yards. As the round has a 250 yard zero, there was no holdover. That wouldn't have been the case with a 45/70, though I have no doubt with a similar high shoulder hit, it would have been just as deadly at the range I was shooting.
