Surplus Ammo 7.92x57 Question

[MauserMike]

I was recently given a small amount of surplus ammo.

From left to right - Israeli, German '42, German '44. I have to find a website for the manufacturing letter codes but does anyone know if there is significance to the red and blue markings around the primer holes for the German ammunition?

I was told this is all pretty "hot" ammo. Steel cases, jacketing on the Israeli is not copper.

 

[SDC]

The red primer annulus signifies AP (hardened steel core), while the blue annulus signifies an iron core.

 

[Hitzy]

It would be a cupro nickle jacket on the israeli bullet (I think). The swiss used nickle jacket for almost 100 years with their 7.5x55.

 

[SDC]

Forgot to add; the left-most round is actually Czech ball, manufactured in 1951; the curved bar shows this is Berdan primed ammo, with one flash hole.

 

[Dosing]

http://users.swing.be/sw017995/german-codes.htm