When were unfluted firing pins modified / replaced ?

[Sieger]

Originally Posted by Norme

Hi Stu,
I think the fluted firing pin modification was in response to the introduction of steel cased ammunition late in WW1. Steel cases did not expand as much on firing as brass cases did and gas leakage became a problem.The firing pins of many Imperial Lugers were modified in this way after the war by the armorers who converted them for Police or Navy use. I know that fluted pins were standard on all Mauser and Kreighoff Lugers but I don't know about Simsons, perhaps Ed will fill us in.
Norm

Norm,

I was unaware that steel case German Army ammo was introduced in WWI.

Also, at least for Mauser's war production Lugers, flutes were designed to clear debris not to vent the breach block area.

Respectfully,


Sieger