The world of custom firearms often feels like a secret handshake among those in the know, but every so often, a build drops that demands attention. SK Guns, through its Custom Works Division, has announced the SK ACE 311 P365 series, a pair of highly specialized pistols that take the ubiquitous SIG Sauer P365 platform and stretch it into something entirely new. This series marries the concealed-carry pedigree of the P365 with the handling dynamics of a full-size, double-stack 1911. The result is a duo of pistols—the SK ACE 311 P365 Fuse Comp and the SK ACE 311 P365XL Macro Comp—that seem determined to defy categorization.

At the center of this entire endeavor is the radical Icarus Precision ACE 311 grip frame. This component is where the philosophy of the build truly takes shape. Icarus Precision has essentially grafted the full-size grip geometry of a 1911 double-stack onto the P365's Fire Control Unit (FCU), giving the operator control "where it counts," as they put it. It’s an audacious blend of two different worlds, and while the idea might sound like mixing oil and water, Icarus’s execution—machined from billet aluminum and featuring aggressive 360° texture—suggests a compelling new feel for a carry gun. With a subtle memory hump for consistent hand placement and a flared magwell, this frame is designed for serious, repeatable shooting, accommodating the 17- and 21-round Macro-length magazines.

SK Guns anchors these builds with the SIG Custom Works P365 Fire Control Unit (FCU). This is a critical detail, as the serialized FCU is the legal "firearm," and using the Custom Works version immediately elevates the pistol's status. It arrives ready for action with an exclusive black nitride frame and a flat trigger, suggesting a clean, crisp break right out of the box. Beyond the improved componentry, these units feature custom "FC" serial numbers, adding a small, appealing touch of bespoke manufacturing. SK Guns' Custom Works Division then takes this premium foundation and integrates a host of precision components to deliver a "turnkey range ready pistol."

The first variant, the SK ACE 311 P365 Fuse Comp, is a collaboration with FDEZ WERX and Icarus Precision, focusing heavily on managing muzzle flip. FDEZ WERX provides the 4.3" FUSE Slide and ported barrel combo, a system designed specifically to work in concert. The patent-pending slide features an extended recoil spring travel and wider port spacing, all intended to deliver superior recoil control and smoother cycling. The non-LCI (Loaded Chamber Indicator) ported barrel complements this by minimizing gas and residue blowback onto a mounted optic—a welcome feature for anyone tired of a perpetually smudged lens. While this configuration is built for performance, SK Guns thoughtfully notes that standard 124gr–147gr ammunition is recommended for optimal recoil control, perhaps humorously suggesting that trying to run blazing hot $+P$ rounds might slightly undermine the entire "recoil control" aesthetic.

The second entry, the SK ACE 311 P365XL Macro Comp, partners Icarus Precision with ARC-DIVISON. This model is built around ARC's Reactor 365X Slide and Ported Barrel. The Reactor setup, designed for the P365 X Macro 3.7" platform, features a relief port placed strategically past the compensator. Like the FUSE, this design is aimed at taming the muzzle and improving the shooting experience. The focus here seems to be on maximizing the efficiency of the 9mm cartridge within the compensated structure, providing a high-quality, button-rifled barrel made from 4150 steel and stress relieved for accuracy. It's a slightly different flavor of performance, but one that is no less dedicated to delivering a flat-shooting experience.

Both pistols share a curated choice of fine parts that complete the custom build. They come standard with XS Sights R3D, 2.0 Tritium Night Sights in a suppressor-height configuration, providing a clear, visible sight picture with serrations and an anti-reflective lens. Furthermore, each build includes an ISMI Turner Pack Recoil Springs Kit with a stainless steel guide rod, offering shooters the ability to tune their recoil system with 13\, 15\, 17\, or 20\ springs—a crucial feature when dealing with ported and compensated slides. Finally, the Align Tactical Offset Extended Magazine Release provides an asymmetric, hardened steel control, giving the P365 a more ergonomic and expedient magazine change capability.

The builds are finished with the Icarus Precision “MACRO” B-ACE pad, a billet aluminum baseplate that adds a touch of welcome weight (0.9 oz) down low, enhancing grip and reload functionality for the 17-round magazines. It’s a small, subtle piece that shows attention to detail, tying the aesthetic of the grip frame through to the magazine. Crucially, the pistols are ready for optics, though they are not included in the purchase price, likely saving the buyer the awkward conversation of choosing between the dozen red dot sights currently on the market. They are optic-ready with SIG-LOC and RMSc footprints (Fuse) or the Holosun 507k footprint (Macro Comp).

As with any custom, high-capacity firearm, SK Guns includes the necessary and slightly obligatory caution: these pistols are not compliant in all states. It’s a stark reminder that while the enthusiast community pushes the limits of design and performance, the landscape of firearm ownership remains heavily regulated. Prospective buyers are advised to contact their local FFL dealer to ensure the pistol can be legally transferred. It’s the final hurdle in getting what are arguably two of the most technically interesting P365 derivatives to appear on the custom market.

SK Guns’ new ACE 311 series represents a compelling argument for maximalism in the world of concealed carry. By fusing the 1911 grip experience with the reliability of the P365 FCU and then adding specialized recoil-mitigating components from FDEZ WERX and ARC-DIVISON, they've created two pistols that are anything but standard. For the shooter who appreciates a finely tuned machine and believes more is simply better, the SK ACE 311 P365 series offers a unique and highly capable option, giving the humble P365 a truly muscular transformation.