World's smallest center fire pistol?

[OKCShooter]

hammer strikes the 2mm primer from the side .. so it's really a rim fire

I thought you were referring to the subject of this post.

The one you posted looks like a pin fire.

 

[_CY_]

a tiny projectile is driven by a primer only .. the primer is struck by the hammer on the side to fire. so technically it's a rim fire
sorry about the crappy pic's .. hard to take pic's of tiny details