Read around a little more & you'll discover that the old "goop up the cylinder face with ball lube" procedure has been proven to have nothing to do with chain fires - poorly fit caps ("pinch them if they're too loose") do.
Ditch the Bore Butter. Go get some beeswax, and then go over to Ralphs, Von's Safeway or whoever still has a real meat counter & ask them for some beef fat. Even in California, they should give you as much as you want for free, since they otherwise pay someone to haul it off.
Add the fat to a pot of boiling water to render out the tallow (which is stiffer than lard). The tallow will float to the top and when cool, hardens. Toss out the rest of the meat & tissue remaining, since even the dog won't eat it.
Boil, melt & cool again to remove any remaining impurities.
Mix 3 parts tallow to 1 part beeswax. It makes a great bullet lube and stays solid in the summer heat better than a lot of other commercial lubes.
While Alox is great for smokeless powder loads, it's not any good for BP.
With a hard alloy such as you want to use, anything with a long bearing surface is going to be difficult to load, and you can eventually break the loading ram arm on your gun. Best to get a benchtop loader, as others have already mentioned.
I've found that even the soft lead .454" Lee conicals to be too difficult to load in several Colts & Remingtons. To use a harder alloy would be frustrating and a waste of time.
If I were still in California and felt compelled to follow all that faux regulatory ¢rap you're compelled to obey, I'd either move, or reload for .44 Mag. to hunt with. Jumping thru hoops to make tin/bismuth work right in a gun made run on soft lead is gonna make you waste time you could be otherwise putting to more productive use reloading or shooting something else.
When you decide to do it anyway, you'll at least have the satisfaction of being able to give the next newbie, sometime in the future, practical advice on why it is folly & won't work.