I am in need of a bit of guidance as to how to go about remedying a troublesome disconnector.

The trigger bar spring on my FCU is forcing the trigger bar to hold the disconnector up so tightly, that it rides up into the recess on the slide, and this prohibits the slide from being removed from the frame, unless I remove the slide cover plate and the striker assembly, thereby allowing me to push the disconnector down and out of the recess.

I took the gun to a smith that removed the FCU from this gun and from another gun that functions properly, and he could see no difference in the two assemblies.

Any ideas as to what I should look for? I am wondering if the trigger bar spring is simply too tightly wound, or its geometry is off a bit?

Any assistance will be greatly appreciated.

What frame are you using?

Is the barrel end of your guide rod a complete circle or 2 half circles? If half circles the round end goes on the barrel not the flat flat end.

I have the full-circle guide rod.

It continues to raise this issue whether I use the FCU in my compact, carry, full-size or Grayguns Xcarry sculpted frame. And also with each of my 3.9, 4.7 or 5" slides and barrels.

...And installing the Apex Forward Set trigger bar didn't help either.

The 320 has had many issues, I would dump it. If not, send it to Sig or Greyguns.

quote:

Originally posted by sg:
The 320 has had many issues, I would dump it. If not, send it to Sig or Greyguns.

OP, if you remove the fcu from the gun, and push down on the disconnector, does it move up and down with a little resistance? Pushing down on it should move the trigger bar down as well, then the spring should push them back up when you release the finger pressure on the disconnector. It shouldn't take a bunch of force to depress the disconnector...just light finger pressure.

If they're not moving freely, I'd start with the spring...remove that and see if the parts now travel freely. If they do, it could be the spring is bent, improperly installed, or one of the legs is out of shape and binding against something. If they don't, you may have a bent disconnector or maybe some foreign object (shard of brass, dirt, etc) has made it's way into the disconnector channel and is binding up the works.

It's hard to troubleshoot without actually having it in hand...but that's where I would start. Has this been a problem since day 1 with this FCU, or did it develop at a later time? If so, what were the conditions that led up to the problem?

quote:

Originally posted by sg:
The 320 has had many issues, I would dump it. If not, send it to Sig or Greyguns.

What do you mean by "dump it"? Just move on from the platform altogether? What do you know of the OP's situation and his ability to even consider such an action? What evidence do you have of these "many issues", their frequency, severity, etc?

These are the kinds of replies that nobody is looking for. "Your gun is trash, you should get rid of it or send it to XYZ company to make right." This is a new member asking, too, and he's in California, which poses its own challenges.

Thank you so much, for taking the time to try and troubleshoot this for me!

I really do like the platform and I have no desire to get rid of it. Out of dozens of flavors of sidearms, my 320 comes in second only to my 229 as to the perfect form and fit for my hand. It shoots really well and I love its modularity and its light weight. I can raise the gun with my eyes closed, and it still has a perfect sight alignment for me.

And I appreciate your understanding of my residing here in the Great State of Confusion... the P320 isn't on the short DOJ list of firearms that are allowed to be sold by FFL's, so I had to find a police officer that had purchased one and then part with $1600 to buy his used gun from him. (They usually run about $2000 here) So, I am clueless as to its previous life.

With the FCU removed from the grip, the disconnector can be pushed down in its channel with about seven pounds of pressure. It only pops back up maybe once in seven or eight tries. With the trigger bar spring removed, the disconnector floats freely within its channel.

Moving the trigger through its take-up, the rear of the trigger bar no longer rides on the face of seer-housing and the disconnector then pops back up with each press. Perhaps the housing or trigger bar has a rough surface. I have a replacement seer housing group coming from Sig that I plan to swap in, and I'll try stoning the current housing and trigger bar in the interim.

Thanks again, for your help with this!

quote:

Originally posted by sg:
The 320 has had many issues, I would dump it.

Tell me that this is advice you would take from a stranger on the internet.

Go ahead. Tell me.

I’m not fully picturing the issue. The disconnector should ride up in the relief cuts made on the underside of the slide. When it’s sitting up in the cut, it is disengaged. When the slide moves rearward, it pushes the disconnector down. That action should disconnect the trigger from the trigger bar and/or sear. I’m actually not familiar with how they accomplish the disconnect within the FCU, so that part may be incorrect.

To make sure we’re talking the same stuff, the disconnector is the bird-head looking thing sticking up out of the FCU, right?

Are you locking the slide to the rear prior to turning the takedown lever?

quote:

With the FCU removed from the grip, the disconnector can be pushed down in its channel with about seven pounds of pressure. It only pops back up maybe once in seven or eight tries.

This is concerning. It shouldn't take anywhere near that much pressure, and it should pop back up immediately with the spring installed. This and the fact that it floats freely without the spring makes me suspect either a problem with the spring or that the spring is improperly installed. Any chance you could take some photos of the spring installed on the gun, and of it removed?

Well, I'm not seeing anything glaringly obviously wrong there. I also took one of my other 320s apart, and while I wouldn't say it requires 7lbs of force to depress the disconnector, it definitely is a little stiffer than my well-worn-in duty gun. That FCU also does not return the trigger bar fully to the top of it's travel when I release it. The gun works and field strips fine, however, so that may not be the root of your issue after all.

quote:

Originally posted by BuddyChryst:

To make sure we’re talking the same stuff, the disconnector is the bird-head looking thing sticking up out of the FCU, right?

Are you locking the slide to the rear prior to turning the takedown lever?

Correct, the 'bird-head' disconnector is being resistant to being depressed, requiring about 7 lbs of pressure to depress the trigger bar, which prohibits the slide from being removed from the grip/FCU.

And yes, the slide is being locked to the rear prior to turning the takedown lever.

Thanks again, for your help...

I'm at a loss. I've never seen a 320 do that, and if it's not the spring, I'm concerned that there may be something out of spec with your sear box, which could create some dangerous problems. It may be time to give Sig CS a call and have them take a look at it. My only experience with them was sending one of my 320s in for the trigger upgrade, and they were easy to work with and turned my gun around quickly.

Stoning all of the mating surfaces on the trigger bar and disconnector and seer housing reduced the pressure required to depress the disconnector to abt 4.5 lbs, and the disconnector returns to its upright position every time now. But the slide still cannot be removed from the grip unless the disconnector is physically depressed. ;-(

I see a trip to Sig in this critter's future...

Thanks so very much for your help!

I may have missed it, but your FCU and your slide have both been through the "upgrade," or were recent enough purchases that both have the "upgrade milling and parts?

I believe you said you're mixing and matching. Does the slide have the upgrade cut?

It is a post upgrade production Xfive. All of the slides are cut.