Closest thing I can see is 7.62 Nagent:
Shell OD (Shoulder Diameter): .453
Shell Length (Case Length): 2.11
Slug OD (Bullet Diameter): .310
Overall Length: 3.02
If you have an interest in IDing cartridges, I'd suggest you pick up a copy of "Cartridges Of The World".....it makes fascinating reading.
Amazon.com has a special on it for $19.57: http://www.amazon.com/exec/obidos/se...894980-0080948