Hey 959,
Both calibers are reloader's dreams. Both respond well to cast bullets.
1,000 cast bullet reloads in the 45 LC, will run you about $150.00, in components.
1,000 cast bullet reloads in the 45/70 will run you about $250.00, in components.
The light load in 45 LC, is a 250/255 gr cast bullet at 750 fps.
The light load in 45/70 is a 350/405 gr cast bullet at 1150 fps. (mine prefers the 405, others have good success with the 350)
Heavy load in 45 LC is a 250 gr XTP, or cast bullet at 1100 fps
Regular load in 45/70 is a 350 gr JSP at 1800 fps.
Stout load in 45/70 is a 425 gr cast bullet at 1600 fps.
Factory ammo for the 45/70 is $2.00/each. (no idea what factory 45 LC is these days)
Hope this helps. (oh, and to do my duty as an "enabler", buy one of each!) LOL
Pics of whichever you buy. (lots of guys have joined MO, saying that they could/would not reload, many of them have since started to reload. You do not save any money, you get to shoot a whole lot more)
Later, Mark