Italian 13.2 x 99 Hotchkiss

13.2 x 99 Hotchkiss from Italy
XI 34
CT is Campo Tizzoro, one of SMI factories.
XI is the 11th lot of 1934
Not sure if the bullet is correct or a nicely made up stuffer.
The case is drilled.
edited after EOD post.
SMI XI 34 CT 50 BMG SMI XI 34 CT 50 BMG a SMI XI 34 CT 50 BMG b

Bob, this is a 13.2x99 Hotchkiss.
The projectile is a self made mockup.

CT likely stands for “Campo Tizzoro” another location of a factory by SMI pre WW2. Some ammo they had they just headstamped. C.T and a 3 digit year (not including the one for 19XX) so would display as 940 for 1940.

After your post i found a bit more info and edited my post.

Bob , Roman 11 = XI represents 6th (Roman VI) lot?

As Hans said, I believe that XI stand for eleven so the case was made in november 1934.

original post is edited.
What year did Italy start producing this caliber?

Italy started producing the Breda model31 heavy machine gun in 1931.
I would feel safe to say ammo started around the same time.

I have two fired cases with unfired Ball projectiles. Projectile length is 62.0mm.

1X S.M.I. 39 C.T.
V BPD 36 S

Drawing 13.2x99mm, Italian AP showing a headstamp date of 1931