WW2 steel case finishes

[BMG50]

I am familiar with the process of German steel case finishes, by either copper washing the case and lacquering after or phosphating and then lacquering. How are America steel shell cases finished are they plated either zinc or cadmium and the lacquered after or not lacquered in the final process. Anyone know?

 

[M8owner]

The finish on the 3 inch Mark 2 M2 B1 cases for the M10 tank destroyer appear to be brown lacquer.

 

[M8owner]

I know there were 37mm M16B1 steel cases for the 37mm tank and antitank guns. I have 3-4 out of 200 M16 cases. I do not believe any have the original finish. There were steel cases (Mark IIIA1B1)for the 37mm Airacobra nose gun - very rare - only seen one. There are thousands of M23A1B1 steel cases for the 57mm AT gun floating around the US since all the dummy rounds used this case, but I do not have one. Many of these dummies were reloaded and fired since there are several operational guns in private hands over here. I have never seen a 75mm M18 steel case for the Sherman tank. There are 90mm M19B1 steel cases for the M1 AAA gun, but I do not have one.

 

[917601]

I have a few Army 3" 1944 Steel cases and rust has bleed through the laquer. I have a 90mm 51 dated steel case and rust has bleed through. Also a few 40mm steel Bofors dated 1953, same. That leads me to believe they were laquered over un treated steel. My Steel 105G 70's dated cases are phosphate with no laquer. No laquer over treated steel. Just my observation.

 

[M8owner]

Here is an example of a 57mm steel cased dummy round. I am not sure of its type of finish as it is not mine.

 

[917601]

Here is an example of a 57mm steel cased dummy round. I am not sure of its type of finish as it is not mine.

I have one identical to the picture. The coloring the same. Much lighter than all the steel cased examples I have, but I always thought the laquer darkened when fired due to the heat. After examining my 57mm, I am certain the bare clean steel was not plated or treated but just a coat of laquer was applied.

 

[bacarnal]

These are some of my WWII and post war US steel casings. All are baked lacquer finish and a few threads in the past have went over the process. They are as follows:

Picture 1
3" MKII M2B1
76mm T19E1B1 (post war)
75mm T6E3B1 (post war)
37mm M16B1

Picture 2
37mm T342 E23 (post war)
37MM M17B1
37MM M16B1
37MM MK1 A2B1

I also have a 1943 40mm Bofors MK3 and a 1953 75mm RR M31A1 in lacquer.
From what I've seen, the US stayed mainly with baked lacquer coating (applied to bare metal) on large caliber steel casings till the mid '50's then went with zinc plating for the most part. Small arms (.30 carbine and .45 ACP mainly) ammunition was zinc plated.

 

[ron3350]

I am a bit late replying but I show my steel cased USA ammunition.
1. Bofors Mk3 RAL 3-55. Cadmium coated?
2 & 3. 37mm M17B1 1943 showing rust affected case and mint brown finish.
4. 37mm Mk111 A2B1 Aerocobra with brown finish.
My M16 B1 case was too rusty to show.
I have different brown and cadmium colored 105mm Howitzer cases too. Some light and darker brown steel cases and varnished coil steel cases.