Sorry, no photos available. so please bear with my attempt to describe these.
I visited a gentleman today who is related to Dick Casull (.454 Casull, etc fame) who showed me three rifle cartridges Dick gave him. Totally unlike anything I have ever seen.
Although the dimensions varied some, all were the same general concept, and totally unmarked. Each had a very large volume brass case, about 15-20mm across the base, and maybe 65-75mm long. They were necked down sharply to calibers roughly 6.5mm 7mm, .30 caliber with very long sharp jacketed (or maybe even solid?) bullets. However, the really odd feature was that all three had a (stainless?) steel sleeve which encased the base of the cartridge body for about 3/8" and then extended back past the rear of the base of the cartridge case about the same distance. The OD of the sleeve was the same as that of the case body, with no extractor groove or anything, so it is not a “belted” type base.
Apparently, to fire, the head of a rifle bolt would fit up inside the recess portion of the sleeve to support the base and reach the primer.
He also has a fuzzy photo of Casull with some sort of prototype semi-auto looking rifle but it was impossible to get any idea of how that might relate to these cartridges, and it may well be en entirely different project.
In conversation, it was brought out that Casull got his start working with P.O. Ackley way back, and apparently Ackley may have had contacts with Elmer Keith in the 1940s, so there are a lot of pretty smart (and opinionated!) guys who may be remotely connected.
Has anyone ever seem any cartridges like the ones described above? What was their purpose, or maybe they were just some sort of gag item made up to stump people? Wish I had photos, but not sure if I can get another invitation to see them or not.