Wolff M10 Hammer Spring

[Maj Dad]

I bought a police trade-in M10-10 from Bud's a few weeks ago, and after cleaning it up (filthy, but cleaned up nicely) decided to replace some springs with Wolff's. I got the Pro-Spring Kit for K-L-N frames, and replaced the factory rebound spring with the 13#, and swapped the factory hammer spring with the Wolff factory spec. When I tested the pull, it would cycle double action, but the Wolff hammer spring hit the rebound slide and wouldn't cock single action. I looked at both hammer springs, and the Wolff seemed to lack curvature at the top near the hooks, so I just put the factory spring back in & it works fine. I called Wolff, and they kindly sent me a replacement, and it did the same thing - so, am I the dummy, or is there something here? I was thinking maybe the Wolff rebound spring might be shorter and allow the slide to travel farther to the rear & impinge on the hammer spring, but I haven't been serious enough to tear it down a third time (so far the screws are un-buggered )...

Any thoughts? It works fine, so it's not a show stopper issue, just a nagging question.

 

[rcmodel]

Beats me?

I have used a lot of them over the years in K & N frames and never had the slightest problem with them.

Only thing I can think of is somebody ground off your strain screw too short to flex it fully.

If you have another K-Frame, exchange the strain screws and see it that makes any difference.

rc

 

[BBBBill]

Same here. Never a problem for me.

 

[Maj Dad]

Strain screw looked perfectly factory (didn't measure it), and felt like it could have been loc-tited when I loosened it. I have replaced all of my S&W springs (M&P, 3 M10s, M13, 686, M1917 and couple of J's) with Wolffs, and never a problem for me, either. If it bothers me enough, I'll tear it down, do some measuring and picture-taking. It is aggravating...

 

[Jim K]

If the factory spring works, why replace it? I have never known an S&W factory mainspring to weaken or break in anything like normal use; the usual reason for replacement is to reduce tension and "improve" the trigger pull.

Note that in some cases, the pull has been "improved" to the point that the gun won't fire.

Jim

 

[Old Fuff]

Be sure they're isn't something in the rebound slide's hole, or the hole dia. at the front is too tight, and keeping the Wolff spring from seating to full depth.

Also Jim is right. If the factory's spring works why replace it?

 

[Maj Dad]

If I take the sideplate off, I'll check everything, but the factory spring is back and will stay unless it breaks. I stopped trying to lighten up trigger pulls with hammer springs after more than one pistol (revolver & semi) failed to fire due to light strikes.

 

[stu1ritter]

I also had problems with Wolfe springs and interference. When I called Wolfe customer service I was told "they never heard that before". I've heard it in my club also. I've stopped using anything but factory S&W springs and the factory springs are cheaper also. S&W parts department has been pretty good lately. I call and order and they show up in a week and the springs are half to one third the cost of Brownell or Midway.
Last order I had sight plungers and springs back-ordered. When they showed up I was only charged for the parts and nothing for postage. That's pretty straight forward.
Stu