Looks like Norinco 5.56 and 7.62x51. The 5.56 is brass and the 7.62x51 is a copper washed steel case. Both are non-corrosive. I purchased a crate of each a couple years ago, the price has definitely gone up since then. If I remember correctly the 7.62x51 is currently being sold retail for around $550/case before tax. The 5.56 isn't available in store anymore although will pop up on the EE from time to time. I snagged a can recently for $200 which was a pretty good deal. I think they ran around $350/case back in 2014.
** I'll add that a can of 5.56 is 560 rounds and the 7.62x51 is 500 rounds. They were sold by the case (2 cans/case).