Why is the 45-70 so popular? Someone said it nicely when they said it's fun. It really is. It's easy to load for and can be loaded for a full range of activities from Cowboy action, to deer, to large dangerous game. I think Wild West Guns custom rifles fueled the resurgence. They were top quality rifles that were gorgeous as they were functional. When Marlin started making their Guide Gun at an affordable price, the popularity really took off. The common man could afford a "Wild West" style gun. The Guide Guns were capable of ridiculous accuracy too.
To my OP neighbor from Houma, That Ruger #3 was known for being very hard on the shoulder. 1895s don't get unpleasant until you start pushing heavy bullets at higher velocity. The guns are handy, fast handing and accurate. The cartridge is versatile and very effective at the kind of ranges most people shoot.