Handy storage is a good possibility, but ...UpTheIrons wrote:Was there ever a military rifle chambered in .257 Roberts? If not, why the stripper clip and 'web belt' that is full of them? Or was that just handy storage?
A lot of Japanese Type 38 Arisakas were rechambered using .257 Roberts reamers, making the wildcat 6.5-.257 Roberts. That let the shooter use US-made reloadable cases with noncorrosive primers in a nice whitetail-class cartridge. It's very close to the 6.5X57 Mauser sporting cartridge in dimension. What's the bullet diameter?
Also, a lot of Mausers, 1917 Enfields, and Springfields were rebarreled to .257 Roberts as well. Removing the stripper clip guide was common, especially on rifles to be scoped, but it wasn't universal.
It's hard to see, but the clip looks more like a brass Springfield clip to me than a Japanese clip.