P320 Modern Classic Slide, 3.9”


Custom Modern Classic P320 slide designed by Bruce Gray and the Grayguns team. This slide features a refined, classic look that complements the modern design of the SIG Sauer® P320. This is the 3.9-inch barrel version created by our team.

Includes custom slide and all internals. Options available will vary. The Complete System Package includes OEM 9mm Barrel and Guide Rod Assembly.

Looking for an optic or sights for your custom slide? Order your choice of optic or sight package and we'll professionally install the optic for free!
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Our custom Modern Classic P320 3.9-inch slide package focuses first on the weight and balance of the slide. We’ve introduced a traditional 1911 spin with utility-driven serrations in strategic areas. Available in a Black Diamond-Like Carbon (DLC) finish. Each custom slide features the iconic Grayguns logo.

As a classic gunsmith, Bruce didn’t want his slide to resemble or feel like a wood rasp out of a woodshop. They went through many iterations but settled on something traditional for this modern sporting pistol.

Slide Package Includes

  • Custom Grayguns Modern Classic designed slide
  • OEM internals (Ejector, Striker Assembly, and Slide Cap)
  • Choice of optic cut or OEM dovetails only

Complete System Package Includes

  • Everything from the Slide Package, plus
  • OEM 9mm Barrel
  • OEM Guide Rod Assembly

P320 Modern Classic Slide – 3.9-inch – Additional Information

You can directly mount one of our red dot options to the slide. There is no need for an adaptor plate.

Fit Guide

If you select the RMR cut, the Trijicon RMR optic will fit fine. Although the Trijicon SRO has the same hole pattern footprint as the RMR, the SRO optic is bigger and will slightly overlap the ejection port on the P320 3.9″ slides.

Additional information

Weight N/A
Dimensions N/A
Slide Configuration

Cut for Romeo1 Pro, Cut for Trijicon RMR, Cut for Iron Sights, Cut for Romeo1 Pro w/ Barrel and Guide Rod Assembly, Cut for Trijicon RMR w/ Barrel and Guide Rod Assembly, Cut for Iron Sights w/ Barrel and Guide Rod Assembly

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Many parts sold by Grayguns - including but not limited to triggers, trigger kits, internal components and spring kits - are intended for installation by a qualified armorer or gunsmith who is familiar with the firearm.

Although kits fit with no issues in a great majority of pistols, Grayguns cannot guarantee perfect functionality in every instance.

Due to varying tolerances present in all mass-produced firearms, professional fitting by a qualified armorer who is familiar with the pistol's action may be required.

Grayguns offers installation services for all parts kits we offer. If you have any issues or questions about the installation process, STOP IMMEDIATELY and contact the Grayguns Customer Service Team.