I guess the reason for the lack of a huge response is that no one has tried it.
I have doubts that it would work though - I think temperature may be an issue and that it wouldn't protect against gas cutting of the projectile base. I only use "off-the-shelf" cast projectiles and all have been hard cast with a synthetic coating (the coating was rated for a velocity of 1700fps, although there are other versions with ratings up to 2200/2400fps, without a gas check). I'm not sure what the coating is but is seems to have a higher temperature rating than the lead itself. I have melted a few down and the synthetic coating remains as a shell of what the projectile once was.
I've also had to use lube on some of these projectiles as the coating has been completely stripped from the driving band part and resulted in eventual leading of the barrel.
By all means if you already have the components and time, then go ahead and try it. If you use caution and check after each shot, then the worst that will happen is that you'll end up having to spend time scrubbing out the lead from the barrel.