If i recall correctly a company called "ashanti" or somthing along those lines made a bolt action shell ejecting 6mm sniper rifle.
Much like the recent tanaka revolver issue these guns ACTUALLY COULD fire a .22 caliber bullet. (if the gun would break upon action and potentially hurt the user I do not know)
That much I am sure of.
What I only vaguly remember is somthing about chinese gangs getting their hands on these & in turn having them being taken away by authorities.
Thats my input - alex