Blueing
 

I noticed on some early lugers that there is an area below the left hand toggle and behind the safety that has an almost ocean blue color. What is this color from and did all of them have this? Thanks, Curt

Curt,

That is the fire blue; it is present on all.

Tom A.

Curt,

To expand on Tom's answer a bit, the "area" to which you refer is the sear spring. On a Luger (pre-1937 Mauser) all the flat springs, the axle pins, the front sight, and the grip screws are "fire blued". This is a natural result of heating white steel to a temperature of about 560�º-640�º F, depending on the color and tempering of the steel desired--the parts differ in their color in this respect. Fyi, the straw found on small parts is accomplished the same way, but straw color occurs at about 440�º-460�º F.

You may be familiar with the effect as seen on new motorcycle exhaust pipes at the cylinder head. The hot exhaust gases at the head turn the pipe very dark and intense blue, and as the gases cool as they pass through the pipe the full spectrum of heat coloring can be seen until they reach a distance where they are no longer hot enough to have an effect on the metal.

--Dwight

I have to hold my 1914 dwm, and my 1916 dwm at an angle to see this blue as it is very faint, my 1918 erfurt does not seem to have any and my 1917 artillery is quite prominently blue. How come so much difference in the brightness? Thanks, Curt

Curt,
I'm sure the condition of each gun is different also. But they all started out the same.
Mike C.