I'm about to pick up one of these switch-barrels in the 12 ga. rifled slug configuration (too good of a deal to pass up - a new gun for the price of a Hastings barrel, and one I can convert to a rifle). However the deal is only on the shotgun, no rifles. Mossberg's available rifle calibers aren't too interesting and I was wondering what'd be the best way to end up with a 45-70 barrel for it.

I'm thinking I have 2 options: Find someone who makes an aftermarket barrel or buy one of the factory 223 or 22-250 varmint barrels and have it rebored and chambered. Am I correct in assuming the sporter configuration of the 243/270/30-06 etc. is too light to consider for reboring to 45-70?

Any thoughts on the feasibility of each possibility, and the $$, are much appreciated.

Thanks. -WSJ

Well I bought it and I can't believe nobody has any suggestions! Help! -WSJ

Since no one answered, I'll give it a shot. Reboring a barrel can be quite expensive when compared to buying a new barrel. You'd have the cost of the re-bore, re-rifle, and re-chamber, plus extractor work (Mossberg doesn't list a rimmed cartridge in their offerings, it may require a one off or modifying a 12 ga. extractor or thinking about the 450 Marlin). Plus you'd be left with the quality of the barrel that Mossberg started with. Not a knock on them, just that they are a mass producer looking to provide a low cost product. I'd look into having one made by a reputable barrel manufacturer or someone that specializes in the Mossberg if it were me.

SmallCal: Thanks for the reply. You're probably right about the effort/expense of reboring. After all, I don't want to have a break-open Mossberg 45-70 that costs the same as a Ruger #1 (might as well just buy the Ruger).

I'll post my question of the single shot forum and maybe someone will know of a source for aftermarket barrels for these guns. -WSJ

What about getting another 12ga barrel, then cut it off to make a monoblock, then thread and solder a .458 barrel into it. You might have to make a custom exractor, but I think it would be doable.