What the heck is this? A 6.5 x 38-55 improved?

[brass shower]

I've come into possession of a quanity of loaded ammunition that appears to be an AI version of the 38-55 necked to a 6.5 mm bullet, it appears that .30-30 brass could be used as the parent case for this wildcat just as easily but I dont see any cases headstamped with .30-30. I'm at a complete loss for finding loading data for this cartidge, much less something it could be chambered in. It would be a neat round for a lever action rechamber job, if it werent for that pointy bullet resting on the primer in a tube magazine. Does anybody have any idea what the name for this oddball is and where I can find more information about it?

 

[deciple-of-keith]

I'm Wondering if what you have there is 7-30 WATERS?or It maybe a 25/35 win.I understand the Waters to be ,just a 30-30 necked down to 7mm/.284 .The 25/35 was introduced just before the 30-30 and suffered for it.Maybe this will trigger some bodies memmory

 

[GooseGestapo]

Most likely it's a 6.5-International Rimmed.

See Speer manual #12, pg467.

It's for the T/C Contender class firearms and is used for IHMSA competiton. The purpose for using the .38-55 brass is that it is perhaps slightly thinner than .30/30 brass and might possibly have larger case capacity to hold more powder. Usually, shooters using this will use the .375 Win brass as it is thicker and stronger.

The particular shooter might have formed from .38-55 as the necks might not have been annealed making initial forming easier, or Vice-versa, might have been annealed making it easier to form.

Who knows ?????

If I were to try to form them, I would use the 7-30 Waters brass, and fireform avoiding the necessity of the extra forming dies.

 

[brass shower]

Pretty sure it's not a 7-30 waters. THe bullet diameter is .264". It's looks like it's got a 40 degree shoulder. I don't have access to a speer manual right now but I took some measurements and compiled this cartridge drawing. Does the 6.5-International Rimmed look anything like this Goose?