There’s been a few discussions about how the Walther PPQ gives off a rattle when you shake the gun, whereas the VP9 and many other guns do not give off a rattle at all, with some concluding that the PPQ is of lesser quality than other handguns such as the VP9.
This impression is somewhat disturbing as I’ve stripped both guns apart completely, and I noticed nothing that would indicate how one pistol is of superior quality in fit and finish than another gun. In fact, I found the PPQ to be more accurate of a pistol.
So what’s the deal?
To get to the bottom of the issue, let’s first measure the actual frame to slide fit of each pistol, and see if it’s true that the PPQ is more “sloppy”.
VP9 slide to frame fit:
Rail thickness – 0.0700″
Slide groove opening – 0.0750″
Amount of play – 0.0050″
PPQ slide to frame fit:
Rail thickness – 0.0595″
Slide groove opening – 0.0620″
Amount of play – 0.0025″
So mechanically speaking, the PPQ has a tighter slide to frame fit and has less play involved. Then why would the PPQ rattle?
The answer lies not in the pistol’s fit and finish, but how hard the recoil spring is pushing the slide against the frame when the pistols are in battery.
The first picture shows the position of the markers when the gun is in battery, I put a masking tape on, then cut the tape with a razor blade between the slide and the frame.
Then I took off the slide lock so that the recoil spring is returned to its neutral position held together by the guide rod:
Difference in distance between slide unlock and locked positions:
VP9 – 0.105″
PPQ – 0.02″
Having to travel 0.1 inch, the higher compression of the VP9’s slide against the frame means there’s a constant pressure pushing the slide up and away from the frame at all times. In fact, it takes about 3lbs of force to push or wiggle the slide against the frame. The PPQ on the other hand, barely applied any force on the frame, making the slide able to wiggle freely.
Does this difference in design determine fit and finish quality? Obviously not. It does raise the question of “would a difference in initial compression of the recoil spring make a difference in felt recoil”? Now that’s a much more interesting question. Almost everyone talk about how the PPQ has a stronger felt recoil than the VP9, but the bore axis on the PPQ is only about 0.1″ higher than the VP9.
Update: (July, 2016)
Having tried a soft recoil spring on my PPQ, I’ve noticed that there weren’t that much of a difference in recoil. The fact remains that the PPQ has a stronger flip than the VP9.
But back to the worry over the PPQ rattle. Conclusion here is that rattle comes from recoil spring placement and strength, not a sign of higher or lower quality on a polymer pistol. Perhaps what’s more important are factors such as accuracy, trigger group, reset, and other factors that actually determine accuracy and longevity of a pistol. All these categories combined still outweigh the higher muzzle flip on the PPQ.