Sig Sauer P320 Custom Works Fire Control Unit (FCU)

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(9 reviews) Write a Review
Was: $399.99
Now: $349.99
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From the beginning, the P320 was built to be a pistol that could adapt to meet the user’s specific needs. From grip modules and magazines to custom slides, barrels, and optics, the P320 can be configured in thousands of different ways to make your P320 unique and exactly the pistol you are looking for.

  • Exclusive Titanium Nitride Frame
  • Titanium Nitride Skeletonized Trigger
  • Custom "FCU######" Serial Number
  • Compatible with all 9mm/357SIG/40SW P320 post-upgrade accessories


  • 5
    Sig Sauer P320 custom works FCU

    Posted by Ryan Lay on May 06, 2022

    The unit I purchased is truly amazing. The shipping if the unit was super fast. (I ordered it on a Wednesday it was at my local FFL dealer on Monday). The installation of the FCU was really smooth. It functions perfectly. I am extremely happy with my perchance

  • 5
    P320 custom works

    Posted by James Johnson on Apr 26, 2022

    Have bought a couple, Excellent product

  • 4
    P320 FCU

    Posted by Joe B on Feb 24, 2022

    This is the only place I could find these in stock and it arrived at my FFL very quickly. Like every other order I have placed here, I got notifications upon shipping and delivery which I thought was nice. The only thing I noticed, and this is focused at the manufacturer and not, is that the trigger isn't as crisp and has a bit more slop than an FCU I handled in the past. I'm not sure if this is due to a redesign from the issues that the P320 has experienced but this trigger at least was not as smooth as I was hoping it would be. Even still, it makes a nice shooter and I would buy it again!

  • 5
    Custom Works 320 Fire Control Unit

    Posted by Tom on Feb 24, 2022

    Love it! Awesome quality and of course versatility.

  • 5
    320 FCU is awesome

    Posted by Paul Lo Verme on Jan 22, 2022

    Really was surprised at the FCU. I dropped it
    Into my handgrip, lubed the rails to my liking and put it together. I compared it side by side with another 320 that I installed an apex trigger in. The trigger in the Sig FCU was just as nice as the custom trigger in my other 320. I was very please. The Ti nitride finish is a pleasure to look at (Gucci as hell) and it functions nicely keeping all of the mating parts nice and lubed.

  • 5
    Delivered to my FFL as advertised without any delay.

    Posted by J.Rizzo on Dec 27, 2021

    smooth transaction

  • 4
    Sig Sauer P320 FCU

    Posted by Zach Teich on Dec 22, 2021

    Simple drop-in installation into appropriate Sig gripframe. Dry firing, trigger is a bit heavier than I anticipated, but it probably will lighten somewhat with use. I can see why these have been so hard to come by!

  • 5
    Great, but pricey

    Posted by Motoman on Jul 17, 2021

    This FCU is a great product. Trigger is light and crisp. Feels very similar to the FCU in my p320 Legion. However, the price is really high. It's a superior product, but for another $100 i could have had a complete brand new p320.

  • 5
    P320 Custom shop FCU

    Posted by Paul D. Jakubson on Jul 15, 2021

    I have been waiting for this product for over six months and it is well worth it. It is expertly crafted and is the building block for my custom pistol.

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