Not a knock but big help so we can hlep you is to have you list your caliber first (308 I take from the end of the post and what specific rifle you are shooting and or asking about. I suspect semi auto but?
List those two first. Then onto the question and issues.
Some powders are also specific for Garrands to function right due to burn rate or other smei auto (308) and sometime they do not publish what the intent was.
In your case you have to watch the loads and burn rates if I am right about the semi auto vry carefully. Internet search can help there as I do not know this powder and 308 semi auto. Its very critical to the function and safety of the rifle (and a civilian semi auto may be more tolerant than the military, not my area) .
Sierra list a 46.7 to 50.2, but that is in a bolt action. It would not be a powder I would go with as its so narrow a small tech difference in a lot of things could throw it off (with the powder shortage I would in a bolt but not one I would choose normally)
Military brass is easy. Its going to have odd stampings and often a date.
Civilian brass is going to have an MFG, caliber but not a date.
LC is a common one these days for military brass and I have a 30-06 one with LC 52 (two digit dates) . HXP 77 etc (that Greek stuff, you will find a lot of European designation in some lots as they made Bunche of it and its got back here.
I could be wrong but I do not think they have the caliber on any of it (at least US calibers) .
Keeping in mind, 7.62 is too different form 5.56 to be confuses and they do not have 20 different calibers that use a 30 caliber bullet.
Again an internet search of head stamps would show you a good examples.
Search 760 powder for 7.62 and you should bet some more info (others will chime in here as well