I feel that the later versions of the interlock are not quite as good at staying together as were the earlier versions.
Don't have a lot of evidence to back this up, since I am a believer in premium bullets for hunting.
However, I did have one sour experience with a 270, 140 grain BTSP interlock on a Whitetail deer.
It was a while ago, and I was in a blind waiting for the deer to show. When a decent buck appeared, I have him one
in the ribs. He jumped high in the air, and hit the ground on all 4 feet, but instead of running, he walked quickly about 30 yards
in behind some willows. I could see a 4" patch of hide behind his front leg, so I gave him another. He obliged by dropping down,
dead.
That first interlock had hit a rib and exploded, with no part of the bullet getting in to the cavity at all. Quite a large shallow wound
on the impact side. The second one missed ribs on both sides, and exited after doing a number on both lungs.
I believe the first shot stunned him, thus the strange reaction. Last animal with that bullet for me.
I believe at slower speeds, they will work fine, but.......Dave.