What is this Modified 264 Win Mag?

[PinonScout]

Came across a lot of 264 Win Mag brass that looks like it would be called a "264 Ackley of some kind but I have never heard of it or find it in my cartridge books.

Its a 264 Case but has an Ackley like neck. I have seen a few internet discussions on it as a possiblity but nothing on ones done.

The bottom of the case is labeled Super-X | 264 Win Mag

attached are some pics

 

[Murray Brook]

Also looks like a Weatherby shoulder. Measure the inside neck to determine the caliber. Could be a 264 Win case passed through a 257- 270 - 7mm Weatherby die.

 

[AccelR8]

I agree it looks Weatherby-ish. 264 Weatherby Magnum?

 

[Dusty Stevens]

It looks more like a soft formed ackley than a weatherby but i cant tell real well

 

[bozo699]

It looks more like a soft formed ackley than a weatherby but i cant tell real well

It does look like a double radius shoulder
Wayne

 

[Tommie]

There’s no such thing as an Ackley neck. More than likely Dusty has this one pegged.

 

[SSL]

Bet it's a Weatherby, like others said. Buddy used to make .257 Weatherby cases from .264. A bit short, but worked.

 

[Will Henry]

The neck is much longer than on a 264 and the shoulder is not weatherby; just partly formed. It almost looks like a necked down 7x61. WH

 

[Zero333]

I think Will Henry might be right about the 7x61 S.& H. Super.

 

[46and2]

I think they made 270weatherby or 7mm weatherby brass out of 264 win brass.

Measure the ID of the neck.

 

[Eric Leonard]

308 Norma maybe. Neck looks pretty fat

 

[Lost_Phil]

What is the measurement inside the neck? If it close to 6.5mm (264), I will have to say its .264 x 61 Shannon.