I've pointed out the following before, but will again:
Core-Lokt bullets have varied considerably over the decades. They originally had heavy jackets along the shank of the bullets, the reason they acquired a reputation for holding together pretty well during expansion. But the Point Soft-Point Core-Lokts (the spitzer model) haven't been made that was for at least 25 years. Remington changed to a thinner jacket around 1990 or so, or started loading other bullets as "Core-Lokts," especially Hornady Interlocks. I know this partly from talking to the guy who was in charge of Remington public relations back then, but partly from pulling "Core-Lokts" from ammo and sectioning the bullets. It was quite interesting to find the Hornady Interlock ring inside some.
But the round-nosed Core-Lokts have retained the heavy jacket sidewalls, probably because there's no much demand for round-nose bullets anymore so the forming dies don't wear out enough to make a real difference in accuracy--and hunters who buy round-nose Core-Lokts aren't all that concerned about pinpoint long-range accuracy anyway. This is partly why the round-nosed Core-Lokts have such a good reputation for reliable expansion and penetration, but the other reason is they're not usually loaded to high velocity anyway, which also helps them hold together. Good examples are the 180-grain .30-06 at the old standard velocity of 2700 fps, the 270-grain .375 H&H at 2690 fps, and when available (it's pretty scarce anymore) the 117-grain .257 Roberts at 2650 fps.
The main point is that "discussing" Core-Lokt bullet performance is kind of pointless because they vary considerably, and sometimes haven't been Core-Lokts at all.
