walther ppk hammer spring on a p-64?

[jebib3]

I purchased a wolf ppk 13lb hammer spring for my p-64. After a lot of effort (at least for me) to replace the 18lb spring I had on it, I am wondering just what I have done? Now, I got to admit that in DA the difference is remarkable! And it seems in SA that it is almost a hair trigger. So at that level I think I like what I have done. But I have yet to take it out to the range so I'm wondering about that unintended consequences thing. Any thoughts from the panel just what they might be? I'd sure be interested before I go out. Thanks too!

[pshootr]

It may be too light for reliable ignition. You can try shimming it with small washers or a piece cut from the appropriate diameter metal tubing if need be. I don't think these hammer springs are rocket science, they either provide the hammer with enough energy to force the firing pin forward with sufficient force to detonate the primer or they don't.
Lightening the double-action trigger pull will also lessen the single-action pull as well. The P-64 has an unusual relationship of double-action and single-action trigger pulls.
Double action is heavier than usual and single action is lighter than usual in my opinion.

[dfunk]

I have no idea why you would want to replace the 18 pound spring that was designed for your gun with a PPK 13lb.
Bottom line: lighter spring = less than perfect track record for reliability and spontaneous mag ejection. The 18 lb P64 spring is the ideal spring for your gun.

[jebib3]

Why I'd want to swap an 18lb for a 13lb is a very fair question. The answer is I wanted to see what the difference in DA would be, simple as that. I do understand the concept of unintended consequences and was wondering what opinions would be if I tried it hence the post. Since then I've taken it out, and with 35 rounds this is what I found (using brown bear ammo): no misfires occured; and no problems with the magazine inadvertantly releasing. However, there was an issue that arose that I never experienced with the 18lb hammer spring: jams on the ejection of the spend casing. Can anyone explain to me if/how this would be an unintended consequence of the 13lb hammer spring? Thank you!

[pshootr]

I wouldn't think they'd be related. Lightening the hammer spring has the same effect as lightening the recoil spring though. Less resistance to the rearward movement of the slide. Are you using the strongest recoil spring that Wolff sells for your P-64?

[gwbiker]

IMO, an 18lb Wolff hammer spring is the absolute limit in SA pull.

[WardenWolf]

Your jams are probably related to the hammer spring, which acts to delay the blowback slightly and provide additional resistance. Chances are the casing is striking the ejector too violently, resulting in it spinning erratically and jamming in the action. It's a similar malfunction to what causes a stovepipe in a 1911.