Note: This video was filmed over a year ago, but I have been holding it in anticipation of the rifle going to auction. That doesn't seem to be happening, so I'm posting the video now.
Only three example of this 1925 prototype rifle from MBT (Metallurgica Brescia gia Tempini) were ever made, and were sent out in hopes of finding military contracts. One went to Norway, and this one went to Russia, where it was acquired by a US Lend-Lease supply pilot.
It is an straight-pull design which is very close to being a self-loading rifle (and in fact additional patents were filed in 1926 to adapt it to self-loading functionality). It uses the standard 6-round Carcano clip, and is chambered for 6.5x52mm Carcano ammunition.
After this was filmed, my friend James took it out shooting again with pre-war brass clips, and said it worked reliably - FWIW.