What is this?

I found this in a box of misc. bought at a gun show. Looks like red primer in bottom with green powder stuck around the sides. It is .391 and .421 long. Thanks; Jack

I am probably dead wrong, but it looks to me like part of a case draw set, or bullet-jacket draw set that someone has played with.

This is a 10x11 Schermer CK Blank,

This unusual cartridge is really a large cup, being rimless and grooveless with a rounded base and open mouth. This cartridge was developed for the

Jackmac-It is a 9mm Schermer Cattle Killer cartridge. There was a big article in a recent IAA Journal about it about 2 or 3 issues ago. I can’t find my copy right now. Maybe someone more organized than me can look it up and give you all the information about it.

I found it in journal #463 Thanks!

Interesting stuff. Don’t know how I missed the IAA article. I usually read them all. Looks like they designed this round simply by using a case draw piece as a pattern. Weird and wonderful.

Now, is this a 9mm or a 10mm - two different answers on the thread?

John–My specimen measures 9.17mm inside diameter and 9.91mm outside diameter, so, 9mm or 10mm would depend on which dimension you use. What size did the IAA article call it?