There are 2 sizes of XTP's .429 and .430, have you tried the .430?
Nothing wrong with shooting lead, most people just dont want to take the time to actually figure out what their rifle/pistol actually needs. Most commercial cast bullets are way to hard, no gas check and the lube is worthless. Lyman#2, with a gas check and a decent made lube, will give you very little problems. I've shot a few hundred and have not had more than a flake of lead come out. There is a decent investment but, some of it can be used for other calibers if you so chose to.
matt