Weak Primer Strikes

[www.prussia.us]

Hey Guys,
The patient is a Mauser P08 mismatch "shooter," not being a
P08 expert I will note for compatibility isues what parts match; frame matching lower, with a non-matching Mauser upper that, and matching Mauser toggle.


Okay I am getting weak primer strikes- 2/3 of time ammo does not fire, ammo works fine when manually ejected and reloaded into the mag and cycled a second time.

Trouble shooting info:
Ammo-new Winchester 9mm,
feeds fine,
toggle assembly all matching but not matching to upper (barrel original to barrel extension).
I removed some oil from the firing pin/plunger/spring area and the situation improved to maybe 2 non firing weak primer hits to every 1 bullet firing fine.

Could this be?:
Worn firing pin, bad spring?????


THANKS