Brass w/WRA Co. headstamp 1918, 4IN, 50 CAL

I have a GIANT 1918 WRA Co. marked brass casing that’s 34-1/2" long, 5-3/4" at the head and the other end is 4" across. I searched all over and can’t find one like it, so I’m guessing it’s rare. I’m new to this, so sorry if I don’t name the parts correctly. I would love to hear some info on this if anyone knows. Thanks, Mark!IMG_1489

A bit of information on the 4 inch/50 U.S. Navy gun:

WRA Co. drawing of the 4 inch Mk VII cartridge case, dated 1898 from the McCracken Research Library, Buffalo Bill Center of the West, WRA Co. digital collection):


Are there other markings stamped into the head (base) of the cartridge case?

Do you know what the rarity factor is on this? I can’t seem to find one either for sale or display anywhere!!

Oh, sorry, thank you for the diagrams!!

I don’t have one but as an example there are 6 different cartridge cases and a dummy round shown in one thread on BOCN ( ) and another WRA Co. 1918 cartridge case is discussed in a second thread on BOCN ( Plus I have personally seen others in collections. So I would wager these are not rare (a grossly misused term) but they are not common.