Game callers made from cartridges

This game caller just arrived in the mail today.

It is made from a cut down 223 shell with open reed fitted as a projectile normally would be (normal 223 shown for comparison). It is supposed to sound like a distressed rabbit or to imitate a coyote howl but I must need a bit more time to perfect the art! I can only get strange noises that sound nothing like rabbit or coyote.

I have seen at least one other variation of game caller made from the deprimed bases of two 12ga shotshells joined together. However these were more of a backyard type product rather than commercially made products.

What other commercially produced examples are sitting in collections out there?