I’m sure they do. I don’t own one or a 30-30. Not very useful cartridges for longer range shots on elk (IMO). I have a Marlin Guide Gun 45-70 that fills the close range thick woods niche. That rifle penetrated a Kodiak bear from shoulder to hip, breaking both. If I wanted to go to something in an AR I’d go with the .458 SOCOM. Very close to the 45-70 in a Marlin.
Sorry to OP for but Wyo what bullet did you use for that brown bear? I’ve watched the damage done to black bears with the 325g Barnes X in 45-70 and often thought that would work exceedingly well on a brown.
To the OP, I would go 350 Legend in the new rifle to be legal in more states. 30-30 should be in a M94 or M99.