Carcano M1938

The Carcano M38 is a weapon seen in Call of Duty 2: Big Red One. and in the teaser trailer for black ops

Call of Duty 2: Big Red One
The Carcano M38 appears in the campaign mission "Operation Husky", but is unusable. It is later seen once again in the campaign mission "Piano Lupo", in which it can be picked up and used. Ammunition is commonly avalible in Piano Lupo, making it an advisable choice to pick it up rather than keep the starting weapons.

Call of Duty: Black Ops
The M38 is seen extremly briefly in the Black Ops teaser trailer, with the words Lee Harvey Oswald in the bottom right corner of the screen but the weapon is never actually used in the game. It was most likely put in for dramatic effect, because of the speculation of the inclusion of Kennedy's assassination.

Trivia

 * The Carcano makes an appearance in the Call of Duty: Black Ops World Reveal Trailer. For a very brief moment, the same Carcano M91/38 used by Lee Harvey Oswald to allegedly assassinate President John F. Kennedy on November 22, 1963 appears, with the words "Lee Harvey Oswald" in the bottom right corner of the page.
 * This is the only Italian rifle seen in Call of Duty.
 * It was high speculated that the rifle would be in Call of Duty: Black Ops as it was the first teaser trailer.
 * The Caranco is very powerful. It will kill an enemy with one shot to the upper body.
 * This is one of the few bolt action rifles in the game the others being the Kar98k and the Springfield.
 * this weapon looks almost exactly like the russian bolt action rifle the Mosin Nagant.