Can anyone ID these

Hi I’m new to the forums. Does anyone know what the two center cartridges are? I added a normal 50 bmg on the left and 12.7x108 on the right for size references.
The center left cartridge is in normal 50 bmg brass but the rounds length is not like other 50 bmg. Is the bullet just seated deeper then normal?
The paint is more blue-green then all the other incendiary ammo i have. I added another picture to show that.
I picked this up from a man who was selling his entire collection and he said he had had it for a few decades but he just did not know what it was.

The center right cartridge i have no idea what cartridge is. The brass says 50 Cal FA 39 but as you can see the brass is shaped differently then 50 bmg. It has a bullet that looks like it came from a 12.7x108 but that does not appear to be correct either.

Thanks for any help,

50 CAL FA 39 case is the T2 experimental case. It’s same length, just fatter.

the Incendiary round looks like it got pushed in to the second canelure.