So, I recently migrated to the P320. I purchased my first sc maybe 2 weeks ago and enjoyed shooting/ carrying it. Fast forward to today and I traded away a couple of safe regulars for a second p320 and 220 Dao sas.

The p320 is filling a role that I have been attempting to fill for some time now. The SCs are about as small as my SP101 but obviously provide more rounds. They are also more reliable than other semi autos I have tried in this size profile. So far, so good.

Today's pickup is a 2016 build with pre recall trigger. I honestly enjoy it from handling and am debating sending it in. I really picked it up as it has night sights which my other model lacks. The goal at purchase was to put this slide on my newer fcu and send the other for upgrade.

However, upon assembly I could not get this combination to work when attempting to dry fire. No click and it honestly does not feel as if the striker is being engaged.

Curious if I was doing something wrong, I swapped parts around a few more times. I got the pre recall fcu to work (function) with both old and new slides. Both fcus were successfully put into both frames. "Upgraded" fcu returned back to original frame and matched with corresponding slide also functioned.

I eventually just took the pre recall fcu and mated it with the other frame (railed) and added the night sight slide to achieve the result I needed to be compatible with the TRex holster that I received today.

This does however bother me as it removes one of the selling points of the weapon system for me.

Can you all think of anything that would help me trouble shoot this? Is it common knowledge amongst the p320 users that post and pre recall firearm components are not compatible?

quote:

Originally posted by kalford:
Is it common knowledge amongst the p320 users that post and pre recall firearm components are not compatible?

Yes.

Pre-recall FCUs will work with both original and upgraded slides.

Post-recall FCUs will only work with upgraded slides.

Sig mills out some material in the slide due to interference.

The upgrade added a disconnector. It kind of looks like a ducks head sticking up out of the FCU. The upgrade included milling a recess for the disconnector. When the disconnector is in the recess, the disconnector is disengaged and the trigger works as one would expect. The disconnector changed the way the trigger reset to a more traditional design. And if the slide is out of battery, the recess would push past the disconnector, which means the slide will depress and engage the disconnector, which disconnects the trigger. So without the milled recess, your trigger is always disconnected.

Thank you for taking the time to respond. I will have to get this one upgraded.

After getting my P320 upgraded and comparing them, there really isn't, in my opinion, any reason not to do the upgrade. YMMV.

quote:

Originally posted by c1steve:
Sig mills out some material in the slide due to interference.

Not technically correct. They mill the slide to make the system function via a slide operated disconnect instead of the original "double click" method.