Unopened and still sealed in the original hermetically sealed tins. 2 tins per crate. 2 crates total. 

These pictures are of the actual ammo on hand, with the exception of the cardboard box, which I pulled off the internet simply to show what is inside the sealed tins. Notice the box bears the same lot # as what is stamped on the ammo here, so it is an accurate representation. I have no photos of the headstamps because the tins remain sealed. Thus, I am unclear of the exact year this was produced. However, the U.S. stopped making the M2 .50 BMG ammo in 1950 and replaced it with the M33 we use today. But the fact these are in 10-round boxes leads me to believe it is probably lend/lease production for the British we sent over there before our involvement, for the use in Spitfires and other aircraft. The U.S. switched to non-corrosive priming in 1953, so these are undoubtedly loaded with corrosive primers.

Each case is $480, but if you buy both, I'll discount that to $450, for a total of $900. That comes to $3.75 a round, which is some of the cheapest .50 BMG ammo you can find anywhere. 

Located in Glendale near 59th Ave. & Cactus