Sig P225/P6 firing pin

DarthNul

New member
I've got a Sig P6 that has light strike issues.

I tried some reduced power Wolff springs when I first got the gun to improve the heavy DA trigger but none of those worked reliably. This was especially true when shooting loads made with "magnum" primers (the only primers I could get for a while).

I went back to the stock spring and things are better but I still get light strikes once in a while which is not OK for a potential carry gun.

When I disassembled the piece for re-finishing, I got a good look at the firing pin and I noticed that the business end was cut straight across, that is, there was no tapering or rounding of the end. I chucked the pin in the drill press and rounded off the tip, being very careful not to shorten the pin. I have fewer light strikes now, but any is too many.

I'm beginning to wonder if maybe the firing pin is too short. Any chance Sig, or a LEO armorer might have blunted or shortened the firing pins on the P6 models so you'd have to keep the super-heavy mainspring in it? This is a 1977 vintage surplus gun but it showed no signs of wear when I got it.

Anybody got a P6 or P225 firing pin handy that they could measure the length? I've looked for a replacement firing pin but I've only found one source, and they say the same part fits the P225, P226, and P228. Can anybody verify that?
 
It sounds to me that you could need a new firing pin, among a few others, as that one could be blunted. If some primers work, and others wont, that tells me that it may be a difference in their seated depth, by design, and the pin wont reach them (unless one cup uses a stronger metal). You might try a thorough cleaning of the slide too, as it may help if any gunk/dirt is causing friction to the firing pin. If there is dirt in the recess cut, on the firing pins body, where the thru-pin holds the firing pin in, it could limit its forward travel. Also, if you take the firing pin out, you could use a round needle file, and extend that recess cut a few thousandths on it rear side, to give the firing pin a little more protrusion out of the bolt face. The last thing is, that if the firing pin spring is heavy enough, and the hammer spring has been changed to a lighter version, the hammer might not have enough inertia to drive the pin forward with enough force, so there are three things to look at.
 
Thanks for the reply!

I ordered a new firing pin yesterday. It was only $15 and that's probably the cheapest way to figure out if my existing one is short or otherwise deficient. It should get here Saturday or Monday.

The next step will be knocking the inner and outer roll pins out of the slide w/o messing up my new Duracoat job. I'll check the firing pin spring against the freebies that came with the Wolff recoil spring "calibration kit" while I'm at it.
 
pins

Case you don't know, Those pins will come out easiest with a special "roll pin punch" that has a small teat on the end to index the punch with the hollow pins.
The dimple on the end of the punch will go a long way to saving the finish on your slide too.

Also, the pins should be replaced with new pins.....using the old ones over is not recommended.
 
I've got a set of roll pin punches and a set of roll pin starters too.

I keep new pins on hand since they'll fit all my Sigs. I may re-use the ones that are in there though, since they're only a few months old and their ends are already painted to match the slide.
 
The new firing pin arrived yesterday. The new one is only .002" longer overall compared to the old one. I doubt that'll make a difference. With the slide disassembled and the firing pins pushed fully forward (no spring or safety block in place), the new pin protrudes .100 past the bolt face. The old pin only protrudes .077. That is significant. These measurements remain the same with the slide fully assembled. I hope this solves the problem.

I plan test it with the ammo it had the most trouble with: Some 100 grain frangible hand loads made with CCI magnum primers. "Regular" CCI SP primers are supposedly harder than most others, and the magnums are even harder. The gun failed to ignite these rounds at least 20% of the time. Failure rate with anything else was <1%. If I can get a couple hundred of the problem rounds through without any misfires I'll declare it fixed.
 
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