If it wasn't 4 badluck, I'd no luck with guns :( DEAD STI

[JonF]

That almost looks too perfect to be peening and the link shouldn't swing down that far either. Likely the cutting bit that coutoured the ramp face just kissed the barrel shank. If the link was too short or the ramp surface was too high, it could be "Stretching" the link to failure as the slide stop pin rides the ramp and tugs on the link. With the link broken, its hard to test these things out though.

[kirbinster]

That almost looks too perfect to be peening and the link shouldn't swing down that far either. Likely the cutting bit that coutoured the ramp face just kissed the barrel shank. If the link was too short or the ramp surface was too high, it could be "Stretching" the link to failure as the slide stop pin rides the ramp and tugs on the link. With the link broken, its hard to test these things out though.

Yes, you are correct. Randy said that would not have been the cause. But heck, what do I konw, it was just a guess.

[bountyhunter]

Can you get a pic of the broken surface of the metal? Either piece? It might give a clue as to why it broke.

I had posted one at the top of the thread, but I have another one. I had not looked at this one previously in any depth as the focus is not great, but I think it shows the source of the problem. It looks to me like there is an indentation on the bottom of the barrel where it appears the link has been smashing into the barrel. I would guess that is what caused the failure.

does look like it.

Edited April 29, 2015 by bountyhunter

[Nugget]

That divet is where the end mill touched as they continued with the lug radius cut. Not from link. If the link was too short and hit the radius you would feel it as it went into battery.

Edited April 29, 2015 by Nugget

[Dustint21]

That divet is where the end mill touched as they continued with the lug radius cut. Not from link. If the link was too short and hit the radius you would feel it as it went into battery.

This is the correct answer.

[kirbinster]

Yup, you are correct about the end mill, according to Randy at STI. Hey, it was just an idea but I guess I was wrong.

[MrWallace]

I don't think that's an end mill kiss or else there wouldn't be a lip left over from where they cut the radius?

[kirbinster]

UPDATE: Got barrel back today with link replaced. They said that the original link was too short which is what caused it to break.

[45 Raven]

While the part failure is unfortunate, I would give a big tip of the hat to STI for how quickly they responded to the issue, how well they communicated regarding questions about the mode of failure, and how short the turnaround time was before the problem was resolved.

I only own one STI (a Tactical 5.0 in 9mm) and had a minor problem with feeding when I first purchased it. STI was quick to provide a remedy and the pistol has run flawlessly. I am very happy with it and hope someday to own one of the new DVC Limited pistols.