That was a very popular thing to do to Rollers over the past 30 years. The 7mm was preferrable because the firing pin was already a small one and didn't need to be shimmed out like the older rollers.
Both Navy and Numrich sold barrels for such conversions. Even forestocks, inletted for the barrels.
You got to see it and judge it. It could have been the deal of the decade. I get leery of what barrels were used, and how well the gun is chambered, etc. I made the mistake of paying almost a grand for a really nice looking reworked lo wall that had a ring in the chamber that can't be seen with any amount of looking. I have seen beautiful guns built on rollers that had one or another problems. About 30 years ago, you could send a roller action to an outfit, (IRRC in New York state) to have it case colored the old fashioned way with Cyanide.
