Well, I'm new here because I figured you folks may be able to answer a question or two and tell me if I'm on the right track.
I'm ready to order some springs from Wolff for my purchased new 4006 and was wondering:

Recoil Spring:
If I increase the factory 17 pound recoil spring to 18 pounds, will it decrease the felt recoil with factory ammunition or just reduce battering of the frame?

Hammer Spring and Trigger Return Spring:
My local gunsmith measured the trigger pull for me and said it was 12 pounds in both single and double action.
I want a little (?) less pull to compensate for short fingers and Hogue grips.
Will going from a 20 pound hammer spring to an 18 pound spring and a 3.5 pound return spring to replace the 4 pound factory spring yeild a percievable difference and still retain reliability? Can I go any lower?

Thanks, I hope someone has tried this already and can save me some grief.

I'll try posting this on a Glock forum.

I've been down that road as a younger armorer.

Want some free advice? (Meaning it's probably worth less than you're paying for it. )

If you're ever planning to use the 4006 as a defensive weapon, either for carry use and/or for home ... leave it in stock condition as far as the springs you've mentioned are concerned. Learn to shoot the gun.

FWIW, when you start messing around with spring rates, you start affecting feeding timing and other things. A heavier recoil spring is also going to cause the slide & barrel to snap back into battery with more force than intended, meaning the barrel is going to be hitting against the slide stop lever's pin harder than originally designed.

A reduced power drawbar plunger spring (sometimes called a trigger return spring) is the only thing that tensions & lifts the tail of the drawbar upward so the gun works as designed. Throw in a lighter spring? Who knows what may happen if the gun becomes heavily fouled inside the frame? Who knows what may happen if the lighter drawbar plunger spring weakens sooner than you might wish? (I've never heard of a factory drawbar plunger spring wearing out, for that matter.)

Light mainspring (hammer spring)? Maybe you'll find the balance between the hammer's force and reliable primer ignition, and won't happen across a lot of hard primers ... or your firing pin channel won't get liquids inside it which attract fouling and congeal into sludge and heavy gunk, reducing your hammer's impact force. (I've seen that happen with enough improper cleaning methods done in duty guns and even standard mainsprings, so you may be taking even more of a chance with an even lighter spring).


Now, if it's only going to be a range/leisure/sporting pistol? Just want something tuned and fun to shoot on a target range? Why not call the Performance Center and ask about their 3rd gen pistol gunsmithing package.

Just some thoughts.

BTDT. Don't plan to do it again (but then I only use my 3rd gen guns as dedicated defensive weapons, so I have no interest in one, or use for a gun set up for target/gaming use).

__________________
Ret LE Firearms inst & armorer

I would be surprised to find that both SA and DA pulls are 12 lb on your gun. The DA pull I would believe but the SA pulls on this type of gun is usually around 5 to 9 lb max.

The recoil spring change you are suggesting is very minor and IMHO will not affect your felt recoil. It may affect ejection and cycling with lighter loads but unlikely.

Reducing the trigger return spring power will directly affect both the DA and the SA pull. However even the lightest spring Wolff sells will at best reduce the TP by 1 to 2 lb. The warnings of the previous poster are valid. You may affect the trigger reset reliability of the gun if it gets really fowled.

Reducing the hammer spring power will also affect both the SA and DA pulls but more so for the DA pull. If you go too low it will affect primer ignition reliability.

The spring changes you are contemplating will probably reduce your DA and SA TP by 1 to 2 lb at most. From my experience the hammer hooks on S&W pistols are cut so pulling the trigger will slightly cock the hammer before the sear breaks the hammer hook engagement. The only way to fix this is to adjust the hammer hooks - this should only be done by a competent gunsmith. The only other thing that can be done is to reduce the force of the sear spring but that should also only be done by a competent gunsmith. Fooling with either of these things without knowing exactly what you are doing could make your gun very unsafe.

Thanks for the info. As it will be a SD pistol, I'll keep it stock. Glad I didn't go too far too fast.