The Sig Sauer P320 took the gun world by storm when it won the U.S. Army’s XM17 Modular Handgun System competition in 2017. The P320 became an instant classic as the U.S. military’s new sidearm, and on the civilian side, the serialized trigger group allowed users to swap barrels, slides, and frames without purchasing new “firearms.”
The gun is a great choice for home defense and concealed carry, but there have been reports that reliability can suffer when users suppress the P320. Outcomes have been different depending on the suppressor, the ammo, and the P320 model, and Mark Miller didn’t experience any reliability issues when he suppressed the P320 RX Full-Size with a GSL Stealth suppressor.
But users on the Sig Talk forum have reported some issues, and it’s not uncommon for striker-fired handguns to be picky about ammo with a suppressor hanging from the front.
Enter the Grey Ghost’s aftermarket P320 lineup of slides and barrels.
If you’re looking to upgrade your P320 with top-of-the-line parts, Grey Ghost’s offerings are a great place to start, and we got a chance to fondle them for ourselves at this year’s Primary Arms Range Day.
Company reps told us that the Grey Ghost GGP320 slides and barrels have been engineered specifically with suppression in mind. The slides are machined from 416 stainless steel for tighter-than-factory tolerances and can be had with a variety of serrations, texturing, and window cuts.
Grey Ghost slides are also compatible out-of-the-box with the Leupold Deltapoint Pro, the Trijicon RMR, and Sig Romeo1, and the Sig Romeo1Pro.
The company also offers match-grade threaded barrels for both the compact and full-size P320. The barrels are machined from 416R stainless steel and black nitride finished. They’re optimized for suppressor use, and like the slides, machined to the tightest possible tolerances for increased accuracy.
We can confirm that the aftermarket parts make a noticeable difference in how smoothly the gun cycles and put rounds down range. Combined with the excellent P320 trigger, the GGP parts make shooting Sig’s famous handgun even better.
These parts aren’t cheap. Purchasing a GGP slide ($420) and barrel ($185) will set you back about as much as a complete P320. But since Sig has started shipping the P320 fire control group by itself, you can build a custom P320 using aftermarket parts without purchasing a complete gun first.
For many gun owners, this was the most exciting part about the P320 design. Like the AR-15, Sig’s handgun can be customized to fit a specific application or need, and the GGP aftermarket products could be a central part of any high-end custom build.