I have had my 320 back for a couple of weeks following the recall repairs. It seems to me
to have quite a bit more recoil, especially on
the trigger. Have any others of you 320 owners
experienced this?

First off, welcome. Second off your sentence doesn’t make sense as written. Are you saying the trigger pull weight is increased? What you wrote is that you felt more recoil in the trigger which is nonsensical. I have sent multiples in and when they return the gun functions in EVERY aspect +/- the same. No double click. Trigger is a little better or little worse. Nothing to speak of. They are just as accurate, just as reliable, they just now have a skinny trigger and a shiny spot in the slide.

I hear some complaints but truly I discount them almost out of hand. Sig arguably handled this in a way guaranteed to annoy many customers. Some of this is justified some is not.

Honestly to answer your question I see ZERO possible way that your gun could have more recoil after the mod. ZERO. You are imagining things most likely.

I know it doesn't make any sense, but it actually hurts my finger when the recoil hits my finger.
I do not have a trigger scale, but it does not seem to me that that the trigger pull has changed.
Accuracy it about the same, and all else seems about like before.

Ok, starting to make sense. It sounds like you might be experiencing “trigger sting”.

That’s not more recoil that is a feedback you are getting through trigger. Some people shooting the same gun will feel it, some won’t.

I would modify title and ask for help with trigger sting. I am no help because I have never experienced it myself.

Thank you for the new-to me- term. I did a google
search on "trigger sting" and got lots of hits.
There is another forum called Sig Talk and several
320 owners commented on experiencing trigger sting when they got they guns back from the recall.
Unfortunately none offered a solution.

Have only had my 357Sig P320C out twice since the update. Definitely more trigger sting than there was before. Haven't done anything about it, will see if it improves with some more range time.

Alright I am in unknown territory but I have read stuff. Lol. Trigger sting can be alleviated or cured sometimes by things as simple changing temperatures (cold is worse), changing grips, moving trigger finger on trigger.

Good news is you might solve this by something as simple as moving up or down in grip module size.

As the story goes, a fair number of people experienced "trigger sting" on the early model P320's. SIG even designed a replacement trigger that was said to reduce the affect, they called it the "adverse trigger".

Most people I've seen comment on this topic specifically in regards to the voluntary "upgrade" have said that the upgrade reduced or eliminated trigger sting, but everyone is different, so who knows.

Here's one thing to try. Make sure you consistently have a firm, high grip when shooting (and dry-firing).

I've found that there is a "sweet spot" molded into the grip. While it's the most natural and comfortable fit when gripping, it can also be a little low. Make a conscious effort to ensure a high firm grip and see if it changes the stinging. I always use a high grip when shooting all of my handguns. However, I have a friend who will tend to throw shots low with his P320 when we practice. I yell at him and tell him to grip the gun higher. Solves the low hits.

Regarding your issue. A low grip will also move the trigger finger lower on the trigger itself. I also played around in dry-fire with my P320 when the trigger sting and double click problems were being discussed here on SF. Could not replicate it with the stock pistol (Jan 2015).

However, I now have the GrayGuns PELT trigger installed. With it, I am able to replicate the double click depending on where I contact the trigger face. My gun has not had the upgrade.

With the new upgraded trigger you may have the same issue described above. One way to find out.

Welcome to the forum.

Yes, the first time I shot my full-size P320 45 ACP after the upgrade it was cold outside and I had definite trigger sting after 20 rounds. The second time it was warmer, and I only had a bit of tingling.

I did not experience trigger sting with my upgraded compact P320 9 mm Luger.

The actual trigger pull weight on both pistols was a bit less after the upgrade.

I had four P320s at one point.
I divested myself of three of them, all compacts, all FDE...
9mm, 40SW, and 357SIG.
I still have a full size 9mm in basic black.
I have been in no hurry to send it in for the upgrade, not sure if I will send it in.....

I really don't know what the problem would be. The trigger releases the sear then the slide moves rearward, depressing the disconnector. The disconnector takes over the sear until the trigger is let out to reset.

Usually trigger sting comes from excessive force imparting feedback through the trigger, like an over gassed AK. In the AK, the BCG can push the hammer back so hard it pushes the tail of the disconnector against the back of the trigger, which pops forward, causing the sting. But I'm not so sure about the P320 operation, because I don't want to take the FCU apart and look inside the housing only to have a helluva time getting it back together. But I don't get any trigger feedback from recoil on mine, much less trigger sting.

You sound pretty sure that the sting is happening on recoil, but is it possible it's happening on the trigger pull? Could it be the geometry of the trigger digs into your finger? I don't see how it could get pinched behind it, but is that possible?

Trigger sting...is it the same (or similar) as trigger slap?

I've not shot an upgrade 320 but looking at these skinny low mass 320 triggers makes me wonder if these exhibit the same sort of pain sensation like the short triggers do for some (like me) that SIG uses in classic P-series pistols.

The VP9 caused me trigger finger pain as well, but that was a different issue caused by contact with the trough at the bottom of the trigger guard. That could be moderated by adopting what for me was an unnaturally high position on the trigger shoe.

My sense is that with the P320 the problem is caused by vibration propagated down the trigger shoe during recoil. This is independent of position of the finger on the trigger.

The original P320 trigger caused the same issue for some shooters. It had a hollowed out back face all the way to the tip. SIG modified the design with the adverse trigger which both of my P320s had before the upgrade. One of the differences with the adverse trigger is that it was filled in (had a solid section) at the tip. My guess is this solid portion served to damp vibration. I never had any issues with the adverse triggers.

The new reduced mass trigger is not only physically thinner, it is once again hollowed out all the way to the tip of the shoe.

I have tried the SIG reduced reach or short trigger on one of my P229s. That trigger does not produce anything like the same sensation. But it did have a tendency to want to pinch flesh between the back of the trigger shoe and the frame because it placed the trigger finger closer to the frame. The new P320 trigger does not place the trigger finger any closer to the frame.

Try one of these:

Sig Flat Trigger

I suggested this before when discussed but got no pro/con response.

Has anyone considered filling in the hollowed out upgraded trigger to deaden the vibrations? A little silicone or epoxy? I doubt it would effect the disconnect upgrade.

The whole purpose of the lightened mass on the trigger was to reduce inertia to prevent discharge when dropped/struck. Adding weight with epoxy back to the tip of the trigger where it can offer the most leverage is completely contrary to the upgrade.

I understand that, but with the upgrade the P320 received FCU and slide modifications that it didn't have previously. Just a random thought from a non engineer.

Maybe Bruce Gray will weigh in on that...

I will try to answer several of your post. I was shooting in cold weather when I experienced the trigger finger. My 320 is a full sized 9mm, and I was shooting 115 grain standard ammo.
I think if a lot of folks are experiencing this problem we should not have to go to Bruce Gray for a fix, Sig should correct it. It has been raining and snowing in my neck of the woods for the last few days, so I have not had a chance to try changing my grip as suggested by a couple of you. I would be interested in other reactions to my suggestion that Sig offer a fix though.

My suggestion of Bruce Gray weighing in is because he played a major role in the SIG P320 upgrade. If anyone would know, he would.