Interesting that Ruger chambered the No. 3 in .30-40 (.30 Government) but mine was in .223.
The first few years of No.3 production was in "nostalgia" cartridges, .45-70, .22 Hornet, and .30-40 Krag. .45-70 was most common. I have heard (but cannot verify) that for every 10 .45-70s they made one Hornet, and for every 10 Hornets, one Krag.
later, they added the .223, and the .375 Win chamberings, and I have heard (but never seen one) a .44 Magnum chambering as well. I have a .45-70, a Hornet, and a Krag. The Krag is marked "200th year of American Liberty" (1976).