Anyone out there who has built one on a ' 98 action? I like the round and think it might be fun to try and work up some loads in a bolt action.
I had been thinking of a 22" barrel to get a bit more velocity than the 18-1/2" bbl Marlin uses.

Hmmm....
I had a 45-70 in a big Siamese Mauser with a 26 inch barrel, sold it ..... to me it was little more than a curiosity; HOWEVER,

I believe Marlin makes a " cowboy" version in the 45-70 or 450 Marlin that has a longer barrel. Now you have the best of all worlds: strong cartridge, long enough barrel to capture its full power, a strong action (okay, its not a Mauser) and rapid fire capability. That' s the direction I would go provided I' m correct on the " cowboy" model.

Never Go Undergunned,
EKM

No thanks, I don' t much care for levers.
Not that I don' t like them just for me the feel just ain' t right. Besides for a manually operated action I' m more used to bolts than levers.