Feeding P08 and P38, 115 FMJ Bullseye
 

I have a 1918 Erfurt P08 and a 1963 P38 with an aluminum frame
I took them shooting using my standard WWB equivalent load
115 FMJ, 4.6 grains of Bullseye and OAL 1.150.
They shot fine, same recoil and report as WWB.
But now I search and see suggestions to drop back to 3.7 or even as low as 3.5 grains.
Is this because of the age of the weapons or the Luger design?
At some minimum load, I am sure they will stop functioning.
Thanks

Photos

I think if its working, I'd leave it alone. However, when I used to reload I used to start light with a handful, then go higher until I had a reliable reload that was easier on the old action. However, many times folks say use WWB because its already an easy load.

I know that the aluminum frame has a reputation of cracking until there was a fix. I would have to look up which ones were affected and what the fix was.

You may not have much luck with lighter loads in the luger, they need good recoil to function;
however, I would go with the lightest I could in the aluminum frame P 38.

The P 38 is more forgiving so you should be able to get a reliable lighter load.

Luger design is quite strong (stronger then the P38, and the Beretta 92 for that matter). Biggest issue is really old age.
Any working firearm can and will break parts with the passing of time.

One of the reasons I select for shooters late Mauser made P.08s. They are also old, but not as old as WWI vintage pistols.

P.1 Frame Reinforcement Hex Pin
 

The P.1 / Alloy framed P.38 pistols had to be reinforced with a hex steel pin due to frame damage caused when higher power loads (think +P or Nato power rounds) were used. It was placed just above the trigger guard.

Early pistols were retrofitted, later ones came this way from the factory.

I've marked the pin in RED in this picture:

mine does not have this feature. :eek:
I guess I will start a ladder down on powder loads to find a minimum working load.
I do not want to blow up these guns!

If you are using a load equivalent to WWB there should be no problem in your alloy frame P38. WWB is well below NATO standards.

If you have developed an equivalent WWB 115gr load, I would not expect damage to either handgun using your loads. As above, these are old handguns, and they can/will break with usage and time.....they are just machines.