First strike no ignition, 2nd strike ignition...what to fix?

[cclaxton]

A buddy of mine was shooting a match shooting a DA/SA Sig. Probably the 3rd round didn't fire, but pulling trigger again ignited the round. Same thing happened during a second COF. This was factory new ammo.

I am eliminating the possibility of a dud round because it went off the second time...is that a fair assumption?

To me there are four possibilities:
1) He needs to clean the firing pin channel;
2) He needs to check the firing pin and make sure it is not damaged;
3) He might get a lighter firing pin spring;
4) He might need to install an extended firing pin.

Thoughts?
CC

[JV_]

I am eliminating the possibility of a dud round because it went off the second time...is that a fair assumption?Sometimes, a poorly/not fully seated primer will ignite on the second hit.

[David Armstrong]

First thought is try different ammo and make sure it is a gun problem, not an ammo problem.

[ToddG]

I, too, would first look at the ammo.

However, if he's done a lot of dry firing of the gun without a snap cap, he may also have cracked the firing pin retaining pin which can lead to intermittent light strikes due to impeding the motion of the firing pin.

[JAD]

To me there are four possibilities:
1) He needs to clean the firing pin channel;
2) He needs to check the firing pin and make sure it is not damaged;
3) He might get a lighter firing pin spring;
4) He might need to install an extended firing pin.

After the gun does the same thing with different ammo, Occam's razor says (2) first, then (1). I prefer more force in FP springs. Extending pretty much anything is fraught. After (2) and (1) I would seek professional assistance.

[cclaxton]

Thanks,
I am going to recommend he cleans and inspects the firing pin and associated parts. Obviously, if he has a damaged part, replace it. if not reassemble, try different ammo. Then try the other ammo.

Appreciate everyone's input.

Thanks,
CC

[Josh Runkle]

Firing pins aren't that expensive. Replace it. And it very well could be the ammo. Manufacturers are cranking out ammo faster than they ever have before.

[JonInWA]

In addition to what others have said, it could well have been just the ammunition/primer. A SA hammerfall imparts more strength/force than a DA hammerfall, so if the primer was a bit thicker, that could explain why ignition didn't occur with the first DA firing, but did with a subsequent SA firing-if that's what happened.

Best, Jon

[Matt O]

In addition to what others have said, it could well have been just the ammunition/primer. A SA hammerfall imparts more strength/force than a DA hammerfall, so if the primer was a bit thicker, that could explain why ignition didn't occur with the first DA firing, but did with a subsequent SA firing-if that's what happened.

Best, Jon

If it was anything other than the first round in the first mag, wouldn't the initial strike have been SA, with the follow-up being DA?

Two other thoughts:

Was he riding the decocker inadvertently?
If this is ammo he hasn't used before, is he using a super light mainspring?

[cclaxton]

In addition to what others have said, it could well have been just the ammunition/primer. A SA hammerfall imparts more strength/force than a DA hammerfall, so if the primer was a bit thicker, that could explain why ignition didn't occur with the first DA firing, but did with a subsequent SA firing-if that's what happened.

Best, Jon

He was shooting cocked and locked, so all shots were SA.
CC

[cclaxton]

If it was anything other than the first round in the first mag, wouldn't the initial strike have been SA, with the follow-up being DA?

Two other thoughts:

Was he riding the decocker inadvertently?
If this is ammo he hasn't used before, is he using a super light mainspring?


Good question...I will ask.
CC

[shootist26]

I swear I participated in a thread just like this a while back here, but I can't find it.

I also got a bunch of light strikes a few weeks ago with my new P239 all in SA mode. Like 10 light strikes in a box of 50 Blazer brass. It was 100% reliable before that with over 1000 rounds through it, and after that incident I have since put hundreds more with zero issues. I learned that Sigs can be misfired if the support hand palm pushes the decocker down slightly. I was able to induce deliberately induce this on subsequent range trips (it took a noticeable effort to), so I'm still unsure how I accidentally managed to bump the decocker so often the first time.

[shootist26]

I, too, would first look at the ammo.

However, if he's done a lot of dry firing of the gun without a snap cap, he may also have cracked the firing pin retaining pin which can lead to intermittent light strikes due to impeding the motion of the firing pin.

is the firing pin retaining pin a user serviceable part?

[LOKNLOD]

He was shooting cocked and locked, so all shots were SA.
CC

Even the second strike on the rounds that failed first strike? Did he manually cock the hammer back prior to 2nd strike rather than just using a DA pull?

[cclaxton]

Even the second strike on the rounds that failed first strike? Did he manually cock the hammer back prior to 2nd strike rather than just using a DA pull?

You are right...the second strike was a DA pull, not a SA pull. What does that tell you?
thanks,
CC

[Jim Watson]

He was shooting cocked and locked, so all shots were SA.
CC

What DA/SA Sig can you get to a cocked and locked start on?
I would pay good money to have my P226 set up that way.

[taadski]

is the firing pin retaining pin a user serviceable part?


With armorer level skills it is. The older two piece FPPPs and the newer spiral pins are pretty easy to manipulate. The tapered solid pin version is more of a hassle, IME, with more likelihood of buggering the slide up cosmetically. Especially if you aren't using a cup shaped punch.



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