30-06 military blanks

[Tom-ADC]

I was cleaning out my loading room and came across some old military 30-06 blanks.
I have head stamps which I think are rare (at least to me) DEN 43, SL 55 & FN 55.
I know DEN is Denver & SL is ST. Louis but can't find FN anyplace. I don't think this would be the Belgium fire arm company but ???
Any idea how rare these might be?
Thanks Tom

[dominicfortune00]

FN is Fabrique National, the Belgium firearm company.

As I understand it FN made literally tons of ammo in all calibers including '06 for sale around the world.

Best to check with a cartridge collecting site as far as rarity.

[Combat Diver]

At that time the standard Belguim rifle was the SAFN (FN49, 10rd semi auto, father to the FAL) chambered in 30-06.