In all fairness, the rifling of every brand of barrel is different. There's square bottom, round bottom, deep, shallow, different numbers of grooves, gain twist yada yada and that's not considering the variations in bore diameters, twist rates and loading different powders.
Some bullets do shoot better from more barrels than others, but that's not to say that any bullet, or even the Lyman Plains Bullet just won't shoot under any circumstances.
Maybe it has a poor design or lacks proper sizing. However .50 caliber bullets can also be run through a sizing die and shot out of a .54 bore using a sabot.
It's plausible to think that for every bullet there's a bore that will shoot it fairly well, even if that bore hasn't been manufactured yet.
After all, fast twist barrels were developed long before conical bullets were even invented. So I'm sure that many folks back then didn't think that fast twist barrels could ever be made to shoot any good either.