"KS" headstamped .50 BMG

Where do the “KS” headstamped US .50 BMG rounds fall on the rarity scale?

I saw an empty case at an antique shop today for $3.00. Appeared to have been a live round that someone pulled apart since the neck was bent and flared out. It was not worth the $3.00 to me as it was, but I know the KS rounds were pretty low production.



Allegheny Ordnance Plant produced caliber 50 ammunition using the KS (Kelly Springfield) headstamp. According to HWS they manufactured 127,870,560 rounds. That’s a bunch. Other plants produced the Cal 50 in the Billions of rounds so I suppose it all depends on what your definition of rare is.


Live round, untampered with might be worth a dollar a round more than other WW2 vintage common plants in .50. Only a dolllar item otherwise.

Thanks guys. I knew of the factory from HWS (which is out on loan at the moment), but had never actually seen one in person in any form until yesterday. No need to make the drive back to pick up the case then…