HK USP9 reducer plug

I created this Grip Plug for my HK, because it's hard to get HKparts where i live.
so instead of waiting for a Reduced Power Main Spring (10/11lbs), i just reduced the Pretension on the Original Spring(ca.14lbs).

Works pretty great while dry firing, will try it on the range next week (26.03.19)

31.03.2019: 3.5mm Plug worked just fine, less Pull weight, 5.5mm had some light primer strikes with stock firing pin spring.

Original pull weight is: ca. 3.6kg / 7.9lbs ;internals polished

3.5mm reducer pull weight is: ca. 3.2kg / ca. 7lbs -> works, Ammo used: Geco 124gr FMJ & Fiocchi 123gr FMJ

4.75mm should get you to ca.2.9kg / ca.6.4lbs ->not tested yet

Ammo used: Gevo 124gr FMJ & Fiocchi 123gr FMJ


I made it in 2 different "spring-hole" depths.
in the future i'll design one with a special screw in it, for variable settings

Stay Safe