Keep them around, funny how one sometimes finds a use for such things.
Makes me wonder if he was trying to make better handloads for a .38 S&W or 9mm Makarov or something. 9mm Luger is just too straight forward for much experimentation.
The .380 part is obviously not functional. That's probably just the size of the round stock he used. 375 is 3/8". Or maybe that's the size he had to turn them down to to fit inside the die body.
He probably used these to expand the cases deeply. It looks like there's no flare step, though. Maybe he flared the case mouths in a separate step.
I have 2 expanders for 9mm. A 356/360 flare for jacketed and 356 cast, and a 358/362 flare for 357+ bullets. I have 2 expanders in 223, as well, one for jacketed and one for cast with a slightly larger flare step, 224/227. (Size of my cast bullets is 224).
BP | Bronze Point | IMR | Improved Military Rifle | PTD | Pointed |
BR | Bench Rest | M | Magnum | RN | Round Nose |
BT | Boat Tail | PL | Power-Lokt | SP | Soft Point |
C | Compressed Charge | PR | Primer | SPCL | Soft Point "Core-Lokt" |
HP | Hollow Point | PSPCL | Pointed Soft Point "Core Lokt" | C.O.L. | Cartridge Overall Length |
PSP | Pointed Soft Point | Spz | Spitzer Point | SBT | Spitzer Boat Tail |
LRN | Lead Round Nose | LWC | Lead Wad Cutter | LSWC | Lead Semi Wad Cutter |
GC | Gas Check |