Remington .45 automatic ammo questions

[BrotherRockeye]

Would like to know the approximate age and value of this ammo.
On the back of the box it says "These cartridges are adapted to Colt Automatic and Thompson Sub-Machine guns."
also says oilproof on it "this feature permits keeping arms loaded and ready for use without fear of hangfires or misfires"

Thanks

 

[BrotherRockeye]

OK...
anyone seen this type of box before?
is it issue or commercial?
any info appreciated.
Thanks.

 

[Cerdan]

What's the headstamp say? Probably R A and a number...?

 

[BrotherRockeye]

Rem-umc

45acp

 

[Cerdan]

hmmm, that's unfortunately not very informative. The "R A #" style headstamp usually indicates date of manufacture. My usual go-to ammo reference website isn't very helpful in this case.

Typing R397A in google yielded a couple of auction pages, but you've probably found those already. The seller seems to think they're military or police issue. To my eyes though, the packaging seems commercial.

 

[Ganderite]

Sounds like remington commercal from 50's and 60's..