Another odd round.. very very odd.

[Nismosonic]

Hi again,
Has anyone seen one of these before??
I was wondering if it's a round for one of the mid to late 1930's anti tank rifles?
sure is some odd looking things to be found still.

 

[sksvlad]

Wild guess, 300 Winchester Magnum swagged to take a .223 projectile.....

 

[Spaceinvader]

Someones fun with a lathe?