I haven't checked this out for myself, so I have no index of its validity, but I've been told that boat-tails with lead cores as far down as the bottom of the "tail" deform under high chamber pressures. IF this is true, then the boat-tails with solid-copper "tails" shouldn't deform.
Another possible explanation is that most boat-tail bullets are meant for use on paper, not on flesh, and therefore don't have either strong jackets or soldered-in cores.
Two features that attracted me to the new Nosler-Winchester AccuBond bullets are their solid "tails" and bonded cores. I've also noticed that the "tail" seems shorter than those on many other boat-tail designs.
