50 BMG Dummy Round

The cartridge has a 45 degree rim if you want to try orienting it differently, I would orient it like it is.

The 50 BMG (Browning Machine Gun) or 12.7x99 was first used in the M2 browning. A .50 caliber belt fed machine gun, adopted by the US military that is still in use today. Commonly found mounted to armored humvees, helicopters, and other vehicles.

In the US today there are many expensive rifles for sale that use this giant expensive round. At $10 per round it is expensive but surprisingly common to find this cartridge in a gun shop.

UPDATE: I made the bullet stick out of the casing more and rounded the sides of the bullet more.