US 20x110RB Diamond headstamp


#1

Yesterday I got a US 20x110RB Oerlikon S case, the headstamp has the dimaond with a letter in it. I have seen reference to this before, but I cannot remember which factory used it, or what letter it is (I cannot make out the letter as the case is corroded from being in the sea). The headstamp is:

<?> 1943 20MM MK2

I’m sure this is an easy ID for someone, I would be grateful if you could help.


#2

[quote=“Falcon”]Yesterday I got a US 20x110RB Oerlikon S case, the headstamp has the dimaond with a letter in it. I have seen reference to this before, but I cannot remember which factory used it, or what letter it is (I cannot make out the letter as the case is corroded from being in the sea). The headstamp is:

<?> 1943 20MM MK2

I’m sure this is an easy ID for someone, I would be grateful if you could help.[/quote]
This could be Bridgeport Brass Co. of Conn. (if my old brain serves me well) There should be a B in the center of the diamond. M. Rea


#3

Thanks, now you say it, looking at it closer it looks like a B in the diamond, so it probably is Bridgeport Brass Co.


#4
  • @ Falcon: When I wanted to mail you a copy of those US 20mm shell case makers and their markings, you refused me. — Yes, the mark [letter “B” in a diamond frame] means “Bridgeport Brass Co.” from CT [USA]. The company also used as a mark the letter “B” in a small circle and manufactured 20X110RB brass shell cases [Mk2 & Mk4] between 1941-1945. — The same company manufactured between 1940-1942 20mm Hispano [20X110] brass shell cases [M20 & M21] using as a headstamp mark “BBC” or the well-known letter “B” in a diamond frame. Liviu 07/22/07

#5

Cheers Liviu. Do you mean email or post the list? Now it comes to it, it would be useful.