>>64091441
I know that one, and it very lightly wounded him. It really does owe to the way it loads, when you're dropping centerfire cartridges down a tube like that, essentially letting them free fall from a height with their primer ends onto a hard surface, you might just impart inertia to the little anvils in the primers, and that's what happened to him.
This wasn't a problem with .44 rimfire cartridge the original rifle was designed around, and it's not something that'd realistically happen with a later Winchester style magazine.
.30-30 being a rimmed and bottlenecked cartridge, and in a fully enclosed magazine tube where there is no free falling, would make it less dangerous than with the Henry repro, as the case would be almost completely unsupported, leading to very little pressure, and any errant slivers of brass casings are gonna stay inside.
Cleaning up that kind of mess inside of your magazine though isn't gonna be fun though, and better safe than sorry, thus why people go for the polymer tips and lever guns with box mags.