I.D. 9mm/.45 Wildcat

Does anyone know what this is and what pistol shoots it?

OAL: .985"
Rim Dia: .475"
Head Dia: .473"
Case mouth ID: .359"

Made from a .45 Win-Mag case of Starline manufacture.


AKMS - that’s an interesting case. I can’t identify it, but the closest round I can find to it is the .40 Super by Triton. the measurements aren’t perfect against a .40 Super empty case I have, but they are close, except of course for the caliber. It almost looks like someone was trying for a “9mm Super” based on the .40 Super.

A sample Triton-headstamped, plain brass case I have measures as follows:

CL: 0.988"
Rim: 0.471"
Base: 0.470"

Proportionately, the .40 Super is similar as well, with a fiarly short neck like that on your 9mm/45.

I wonder if Triton ever fooled about with the idea of having a 9mm based on their .40 Super?

Not much help, I know, but maybe a starting point.

Could it be a .38 Casull?

NHo, I checked the .38 Casull. The neck is longer and the case is much shorter (0.933 to 0.9365 measured on my electronic digital caliper).

For the same reason, it also can’t be an attempt to replicate the .38 JWH from Australia, which is almost the same as .38 Casull.

Except for a possibly shorter neck, a 350 JAWS.


Ray - if it were not for the neck, we would shout “Bingo!” Measured from my Qual-Cart specimen of .350 JAWS, the measurements are not identical, but would probably be within manufacturing specs for the caliber, without even taking into account that this is made from a different case, not newly made it its present form. Proportionately, the neck is shorter,I am sure from the picture. It doesn’t appear to be an illusion… Then the question is, is the case pictured a new case, or has it been fired? If fired, is it possible that the shoulder was moved forward due to residual breech pressure? Probably not, I suppose, or it should show a bulge at the base of the case I would think. If this were a case from the development of the cartridge, it would not have necessarily had a “perfect” load in the case. Even without that, it is so close to the JAWS that it could be part of the development of that cartridge or the work of a wildcatter trying to duplicate the performance of the .350. Hard to know.

Your “guesstimate” comes the closest of any known cartridge I am aware of. I even looked at my .360 Mars round!


I don’t claim to know much about the JAWS pistols or cartridges, but I seem to remember (or maybe I dreamed it) that the original cartridges were based on the 45 Magnum brass. The shoulder on AKMS’ case appears too sharp to be formed in a die and gives me the impression it has been fired. That, as you said, would/could account for the shorter neck.

Or,as you hinted, maybe we’re all overlooking the obvious - it’s a wildcat.


Sorry, I forgot to mention the obvious. This is a fired case. A friend of mine picked a few of these up at the private range that we belong to. I don’t know of any of our members being “wildcatters”, but I could be wrong, so I suspect that this might have been a factory load or loaded by someone on avialable dies.

The neck length is short, just a few thoudsandths over 1/10" in length and there is trace evidence of a neck crimp. A fired 9x19mm FMJ projectile is a loose fit in the neck, so I presume that it is indeed a 9mm/.38 caliber.

What kind of pistols are these cartridges fired out of? Too long for a 1911 type I would think…



Based on that further info, I’m going out on a limb and say that you have a 350 JAWS case.

Jordanian Armament Weapons System. There are several JAWS cartridges in calibers ranging from 22 to 40, I think.

John can give you a lot more information than I can.


.350 JAWS and Unfired empty