bullet, brand, style and weight
powder, brand, type and possibly batch
brass, brand, number of fired times, trimmed to length
new brass or fired brass
total number of pieces of ammo in that batch
cartridge overall length
primer, brand, type
velocity average
SD
gun the ammo was fired in (I have 3 22-250s. 3 .204s and multiples of others as well)

I also shoot some wildcat cartridges that require case forming and fireforming. I record the process I used to get the best finished brass. I record whether or not I annealed it too.