I wasnt sure if the smaller base would make turbulence/other aerodynamic term that would affect accuracy or not. I dont cast, but I kick around the idea from time to time. The hardcast I use now all comes from a semi-local guy and they are pretty tough as-is without any gas check. I use them in a 41mag with 20gr of 2400 and no leading. The primers seem to dislike that more than the bullets.
I've heard the deal about boattails being more accurate in rifles, but I figured that the more extreme base of the bare gas checked bullets would be too much to allow for accuracy.
As to the original question of using lead in a 454, I dont load for anything that hot, but would a lead bullet be the best choice for that application in a case where the bullet would be going fast enough to need a gas check? If you want to shoot lead to practice on the cheap, I can see using a 41/44mag range load using lead, but for hunting use (which I assume you dont plan to shoot a 454 just for plinking), why not take advantage of those rifle type velocities and use a premium hunting load? I cant see there being expansion problems with a bullet going that fast like there is for most pistols out to any normal handgun hunting range. I love lead as much as the next guy, but every material has its limitations.
Randy