So if someone wanted replacement barrels for an MSR, are you still able to furnish those
I have original barrels for 762, 300WM, and 338. I am mainly looking to not wear the originals out, and to be able to source some for future use.
It's all about the barrel extension, which is something that Bartlein barrels doesn't make or sell. Frank can easily make you a barrel blank, but it would be on you to find a barrel extension for the barrel blank to use. As far as I know, there isn't anyone making the MSR/PSR/CSR barrel extensions (all of these rifles use the exact same barrel extension and bolt heads, I use a .338LM PSR barrel and bolt head in my small prototype CSR rifle). The only place I've ever found them for sale is on Gunbroker (unfortunately it's just this single type of barrel extension):
https://www.gunbroker.com/item/1065620325
Frank will have have to let you know if you can send him the barrel extension to put on one of his Bartlein barrels, or if you'll have to take his barrel blank and the barrel extension to another gunsmith like in
@macethetemplar's posts above. Your best bet is to shoot
@macethetemplar a message and have him get you lined up with Tony Ben to have actual barrels for your rifle assembled. I'm not sure if Frank actually wants to go through this entire process of actually making MSR/PSR/CSR barrels with customer supplied barrel extensions, but as long as you have his barrel blanks, Tony Ben can put them together for you.
Don't be afraid to shoot your original barrels, I shoot mine any chance I can get. Some of the rare prototype barrels are irreplaceable, but other barrels are just Remington barrels that can be shot out and you can have the barrel extension reused on a new better barrel. As long as the barrel extension isn't damaged in any way, the extension can be reused an unlimited number of times on new barrels! So, if you burn out a barrel, remember to save the barrel extension for use on a new barrel. Also, grab some of the bolt heads on gunbroker if you need them, those really come in handy if you really want to switch up calibers. I'm sure that you already have some, but extras are always good too.
If you're having new barrels made for your rifle, you can also have them made in whatever calibers will fit your magazines, barrel extensions and bolt heads (such as 6.5 Creedmoor for the 7.62 bolt head, magazines and barrel extension). I think that
@macethetemplar is even working with a company to have an integral silencer barrel custom made for his CSR rifle! That's a very interesting and unique barrel for these rare Remington rifles! As long as you have the barrel extensions and a gunsmith who's willing to work on the barrel, you can have just about anything made, so don't worry if Frank isn't working on compete MSR/PSR/CSR barrels at this time (hopefully he can give you a definitive answer though).