Sig P226 Off Center Strikes

[Failure2Stop]

As the title imples- the issue is failure to fire, with a prominent off center primer strike. The round will fire if used in a pistol not exhibiting the issue, removing ammunition failure from the troubleshooting sequence. I am seeing this in about 5% of our pistols during courses.

Inspection of the slide shows distinct brass imprint and primer circle off center of the firing pin hole. Barrel and slide interface appear to be normal and the system is in the locked position (not out of battery). I have not contacted the manufacturer as these are issued weapons, thus my normal line of complaint is up to the armorers, who are completely useless.

My initial thought is that the slides are incorrectly machined- however the pistols only seem to exhibit the issue after a few hundred rounds.

I have also seen many whose roll pin are fairly loose and slowly drift. However- these are not always the ones that show off-center strikes, nor are all the off center striking pistols' pins loose.

Anyone else seeing these issues or know the root cause?

[Robb Jensen]

I'd first look at the recoil spring making sure it's strong enough to lock the slide all the way forward. Also inspect the locking block and takedown lever and obviously the barrel lug.

I'm renewing my SIG armorers cert. Mon-Tues, I'll ask if they've seen this problem.

[ToddG]

You mentioned roll pins, so am I correct in assuming these are older (stamped 2-piece slide) P226's? If so, they are (1) old and (2) almost certainly in need of proper armorer attention. It's recommended to replace the dual roll pins every 5,000 rounds. You might try that as a quick possible solution.

Has the problem existed since day one with these particular guns or is it something that cropped up over time? If the latter, it would again be indicative of a wear issue rather than a machining problem.

It's possible the breechblock is not properly aligning with the barrel. Check to see if the slides are cracked, especially at the roll pin holes.

Try swapping barrels between a gun exhibiting the problem and one that isn't. Does the problem persist and if so does it stay with the slide or follow the barrel?

If it's the slide, put the original barrels back in both slides and next try swapping complete top ends between the good gun and the problem gun. Does the problem stay with the slide or the frame?

[Failure2Stop]

Todd, Robb- thanks for the rapid responses.

This is being seen with both "new" and old guns. Apparently the contract here is for the stamped slide guns. I have seen the issue more on the "new" guns- the P226Rs, with the older non-railed ones showing less instances, though they are at a much lower density than the Rs.

I will check up on them as you have both recommended, and will have all the roll pins replaced immediately. I have asked for this to be done on several of them already, but as I said the armorers are pretty much useless.

The guns were inspected for cracks but I highly doubt if they were magnafluxed, most likely only a magnified visual inspection. Swapping barrels and slides here is verboten, I was hoping that this issue had an easy fix or known cause.

I will conduct a detailed test-shoot of our existing stock as soon as possible.

Thanks.

[ToddG]

As a general rule, an unusual problem that occurs over a wide population of guns from different vintages is most likely related to maintenance, ammo, or some other institutional issue rather than the guns themselves. Like ... someone just put brand new locking inserts in all the guns, and they used the wrong insert.

If diagnosing the problem intelligently is verboten, suggest to command that each gun needs to be inspected using the S. L. Edge method. Then just go find a sledgehammer and see if the problem guns continue to have problems after being crushed to pieces. If not, keep using them. If so, they need to be replaced.

If you'd like, for a small consultation fee, I can write that up formally for you to submit.

[markm]

As the title imples- the issue is failure to fire, with a prominent off center primer strike. The round will fire if used in a pistol not exhibiting the issue, removing ammunition failure from the troubleshooting sequence. I am seeing this in about 5% of our pistols during courses.


I've personally experienced these light primer strikes on 2 different p220s. I didn't really notice if they were off center, but follow up pulls of the trigger did not ignite the primer.

With both pistols, I was able to get the round to fire in a different gun.