Got several 320s so, yes, I guess I could just pull the FCU from one, but I have the hankering to build a gun from the ground up.

For those that have done so, have you experienced any difficulties with aftermarket components not playing well with the factory FCU?

My hypothetical build at this point is an Agency modified factory full-size grip (so not really "aftermarket), a Norsso compact length slide, a threaded barrel of some stripe and probably an Agency compensator to bring total slide length just to the end of the full-size grip.

Anyone done anything like this, using mostly aftermarket components to build a 320?

I have not but have you tried searching for "P320 build" on youtube?

Not “mostly,” so forgive the unresponsive answer, but I did acquire the stand-alone FCU and put together a “Carry” model using a Wilson Combat grip module and then 357 SIG and 40 S&W barrels, recoil spring, slide, sights, and magazines from different sources. Only the grip module was nonfactory. The gun I ended up with wouldn’t have been available otherwise in its finished form.

Yes, I have built two from the ground up using the CW FCUs. One is on an AXG module with LOK Veloce grips the other is on a Wilson Combat grip module. Both units have GGI flat triggers with over travel adjustability. I have another CW Scorpion as well as an X5 Legion. I could have moved the other FCUs around but decided not to do so. You really don’t save any money building from the ground up, but I have them set up the way I want and don’t have to swap everything around. My plan is to move my to the P320 for my HD and larger CCW in the next few weeks when my new Milt Sparks leather arrives. I have been training hard with this platform and feel really good with where I am with it. I had zero issues with the parts that I chose to put in all of my 320s. I have various parts from Wilson Combat, Grayguns, and Armory Craft. My slides and barrels are all Sig hardware.

If you want to buy a complete pistol for the FCU and sell off the parts you don't need to offset the price, I am looking for a complete full size 9mm upper group with night sights at a fair price. Preferably a slide that doesn't have the cut for an optical sight. There are some police trade in pistols out there that fit the bill. Let me know if you do.

No but I’ve built 2 365’s from their “custom shop” fcu. An fcu is an fcu, you won’t have any issues. It is the more expensive way to do it though. I like building it my way though so I did it anyway.

Custom Shop, Shmustom Shop: I'm waiting for SIG to offer a standard FCU for sale at a reasonable price. I'm not holding my breath, though.

I have not built from aftermarket, but I did take an FCU and built an entire P320 from a stripped slide and new in the package SIG factory parts.

The pistol went together with no fitting other than having to stone a bit off the bottom of the front sight so it could be tapped into the slide dovetail without excessive force and the assembled pistol functioned perfectly.

Built the lower using the full size Legion grip module. Just looking for the right slide to finish the upper (no stinkin' lightening cuts 4 me).

Here's my P320 X5 Zev build: https://i.imgur.com/muh7t96.jpeg

quote:

Originally posted by toivo:
Custom Shop, Shmustom Shop: I'm waiting for SIG to offer a standard FCU for sale at a reasonable price. I'm not holding my breath, though.

THANK YOU. I was SO excited for the FCU only for it to be an overpriced "custom" one instead of a basic one for 100 dollars less.

quote:

Originally posted by Jester814:

quote:

Originally posted by toivo:
Custom Shop, Shmustom Shop: I'm waiting for SIG to offer a standard FCU for sale at a reasonable price. I'm not holding my breath, though.

THANK YOU. I was SO excited for the FCU only for it to be an overpriced "custom" one instead of a basic one for 100 dollars less.

As was suggested earlier, if you want a cheap FCU, go out and buy the cheapest P320 pistol you can find and then sell off the complete slide and grip as a kit. I have even seen some FFL's getting into this idea.

I have built two from scatch, using the Custom Works FCU.

One was with a Wilson Combat grip module, and a Sig 9mm Compact X-change Kit.

The other is with an Icarus A.C.E compact alloy frame, and a Sig 40s&w Compact X-change kit.

I've found that the FCU is smoother and has a shorter take-up and reset than the stock FCU.

I haven't had any issues with either of them working with various aftermarket parts.


Walker

yes i have and it up for sale in classified. built it than the sa=35 came out. now i am selling it to fund my sa=35 never been fired.

I haven't bought or used the "custom shop FCU," but have built half a dozen with a FCU out of a factory handgun. I've also installed aftermarket guiderods and trigger kits, as well as aftermarket magazines, grip modules, and mixed and matched slides and other parts. I've made several sets of similar full size for competition using the heavier TXG grip module, but my own combination of parts (largely Grayguns), for competition pistols.

A custom shop FCU won't be any different. They all function very well.

The P320 is not a precision watch. It's got enough slop built in that you can throw most parts together and it will run just fine. Improvements are possible (Hence the Grayguns triggers and action kits, sculpted grip modules, fat guide rods, etc). Even with the built-in slop (which lends to excellent reliability), it's still accurate, and it's designed to swap parts and build up without any real loss in reliability or accuracy. Again, the custom FCU won't change that.