I've noticed that in the models coming out recently with full interiors (Meng, Rye Fields, Takom), German ammo cases have to different colors: brass (as expected) and a more steel-like one.

It does add some visual interest to the model, but how accurate is that? And more importantly: what sort of color is that? (Can I mix steel and some gold from AK's true metal, or is there a specific color I can get?)

Thanks

if I remember well at the end of the war with the chronic lack of raw materials, they sometimes used steel instead of the classic brass

The lack of Brass resulted in the German Ammunition manufacturers using steel for large calibre shell casings although they had been using it for smaller calibre such as Flak guns and rifle ammunition for years.

The steel had a coating on the outside, said to be greenish in colour, which tended to jamb the round in the breech after firing. There are accounts of Loaders having to resort to hammer and cold chisel to get them out.

Thank you for the responses!

So a dark steel color would be appropriate? (Black and steel mixture?)

Also: did the mix and match brass and steel casings like in the models I was referring to? Or if the loadout is steel casings, it's all steel?

Now that I understand what to look for I found something interesting

https://forum.axishistory.com/viewtopic.php?t=87234

laquer coated steel ammo

Pics of German and Allied ammunition, WWll:
http://www.quarryhs.co.uk/tankammo2.html
Gives you an idea of various colors and materials of cartridge cases.

Another splendid ressource on both crates and ammo:
http://wehrmachts.kisten.free.fr/categories.htm