Cartridge ID


I need help identifying a cartridge in my collection. It is a .22 cal. centerfire with the same rim and head diameter as the .22 Hornet, considerably shorter. The shoulder is short, but quite steep. The dimensions are as follows: Bull. dia. .222; Case lgth. .892; rim dia. .346; head dia. .295; neck dia. .244. The headstamp reads “R A 5 8”. Any help will be appreciated.


As a ranging shot I would say one of the Morris 297/.230 varients but I would keep that open for other members of forum with a better view. RA doesn’t quite fit and 58 is quite late


The Only .22 Hornet ammo made with a Military headstamp, such as “RA 58” would be the ammunition supplied for the USAF M6
Survival Combination Guns ( .410 Shot and .22 Hornet rifled).

If this is a 297/230 cartridge case, it has been “home converted” from such a case.

WE use .22 Hornet new cases for making the .297/230 Long case for customers.

Doc AV
AV Ballistics
Brisbane Australia


I have been contacted off forum by a very knowledgable friend who suggests this is a Hornet based widcat. Such is his knowledge of these matters that I have no hesitation in agreeing with him. The key really is the short neck and the hard shoulder. If it were a Morris varient the length of the neck would have beeen commented upon because it is very apparant and the shoulder would be very soft because that was the way they made them to be fire formed out into the chamber profile because such things didn’t matter with the Morris varients.
Also the RA58 headstamp is more common on Hornet cases than we may have believed and wouldn’t be considered to be noteworthy.


Could this be the wildcat known as the K-Hornet?


John, I don’t know, our friend is the expert. I am just the messenger.



The “K” is the same length (within a few thou) of the Hornet case (mine has a CL of 1.407), as all the K-Hornet is is a blown out Hornet round (IOW Mr Killbern did for the Hornet what Mr Ackley did for several other rounds IE he “Improved” it)


It could be the wildcat of the .22 Hornet with the name " .22/6//40 "
This cartridge is mentioned in the book “Wildcat cartridges” second edition by "WOLF"
The one in my collection fits to the discribed measurments only mine is headstamped “W-W SUPER 22 HORNET”

Best regards,


Thank you to all who responded. I now have something to go on.


Could be also the 22 Harvey Kay Chuck