I used to be anamored of long range hunting with the .45-70, and wanted a pointed .458" bullet badly. But really, the ballistic advantage is kinda small for practical ranges, and 250-300 yards is a long way. With laser range finders, trajectory goofs in the field are less likely and the existing 300-grain bullets are soft enough to expand at over 200 yards and penetrate plenty. Too, the large flat meplat seems to be a contributor to the highly effective knock down ability of the cartridge.
A pointed bullet will increase the BC, but what would we be giving up if the bullet was too tough to expand? We'd lose the 'slap' of the flat point, and the wound channel would be pretty small with that ice pick point. If the TSX opened enough then okay, but I don't know if it would.
I agree that the 300 Hornady doesn't need the InterLock feature. Back before any Hornady bullets had the InterLock they used the cannelure to limit expansion and to hold in the core. The ones I used worked pretty well. But Hornady saw a need to improve their bullet line, and I can't see where the InterLock feature hurts anything. It probably helps some bullets. But the old-school 300HP worked just as fine 30 years ago as it does today.
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