The SIG P365 XL has become the standard in high-capacity CCW.
(Photo by Alex Landeen)

Introduced in 2017, the Sig Sauer P365 changed everything about concealed carry firearms. Prior to the P365 you could pack a proper high-capacity combat pistol concealed, but it was going to be the size of a running shoe and weigh as much as a world-class bluegill. By contrast, the P365 packed 12+1 capacity and proper combat pistol ergonomics into a handgun you could comfortably conceal underneath shorts and a t-shirt. Our little world would never be the same.

SIG P365 Spy Gun Build

Two years later Sig debuted the P365XL. This variant used the same interchangeable fire control module of the P365 now set into a longer frame underneath a stretched slide and barrel. The innate modularity of the design was custom crafted for upgrades. Nowadays the tactical landscape is littered with cool-guy stuff that makes this great gun even greater.

Grip modules swap easily while offering the option of a manual safety if desired. Ingenious aftermarket American tinkerers developed threaded barrels, light modules, electronic red-dot sights and properly-scaled sound suppressors. The end result is the absolute perfect spy gun.

A Bloody Night

Napoleon Solo stood motionless in the rain, the cold water running over him as though he were part of the inert landscape. He remained in the shadows, invisible from the entrance to the Uzbek embassy. His training and experience as an U.N.C.L.E. operator had transformed him into one of the most lethal human beings on the planet. Underneath his dark gray Burberry trench coat his hand encompassed the grip of his highly-customized Sig Sauer P365 micro-compact handgun.

Solo personally had little use for Karachi, though he had spent enough time there to feel at home. An hour prior he had been alone in his expansive suite in the Mövenpick Hotel, the sundry components of his primary tactical weapon laid out meticulously on the bed. With a familiarity borne of literally countless repetitions he assembled the various pieces, transforming the stubby little concealed carry tool into a high-capacity precision carbine. Now that same customized weapon hung at his side ready to rock.

His target was a senior THRUSH shooter, an inveterate butcher whose operational experience rivalled his own. Mustapha Ajmal Ibn Taymiyyah had murdered his way through the ranks of the world’s most soulless terrorists. Then he touched off a car bomb outside a kindergarten in Moldova. For that, U.N.C.L.E. determined that he must die. Napoleon Solo thus became the instrument of institutional vengeance.

Ibn Taymiyyah struck out on foot to the east. Solo had to hustle to keep pace. Three blocks later the two men were alone. Solo knew it was time.

If Solo Packed a P365

As Solo brought up his custom suppressed P365, Ibn Taymiyyah suddenly spun, a Glock 18 now filling his hand. The Austrian machine pistol vomited 34 rounds in a single bilious burst, liberally peppering the neighborhood with zippy 9mm slugs. Solo instinctively ducked behind a garish parked jingle truck. His highly refined reflexes saved his life, but only just. As Ibn Taymiyyah dropped his empty magazine and fished for a replacement Solo rolled out from behind the truck, steadied the glowing red dot on the terrorist’s heaving chest and stroked the trigger.

The little suppressed Sig pistol coughed out four rounds in quick succession, catching Ibn Taymiyyah center of mass. The inveterate killer of children flew backward, his machine pistol skittering unfettered across the wet macadam. Solo jogged over to the man and dispensed a security shot before glancing around to ensure that they were still alone.

The author shooting his SIG P365 XL spy gun build.

The man from U.N.C.L.E. drew his Microtech Troodon automatic knife and relieved the cooling terrorist of his right thumb, dropping the severed digit into a plastic bag he had brought along for that purpose. Half an hour later he was back at the Mövenpick. Twelve hours after that he was in London. Though it sometimes felt as though he were pushing against the tides, now the world was just a tiny bit safer. Napoleon Solo slept soundly that night.


“The Man from U.N.C.L.E.” ran on American TV for four seasons beginning in 1964. The show followed the exploits of American agent Napoleon Solo and his Russian partner Ilya Kuryakin as they battled the shadowy evil entity THRUSH. THRUSH was an international criminal terrorist conglomerate bent on global domination.

U.N.C.L.E. was left intentionally enigmatic. The show’s writers eventually reluctantly assigned “United Network Command for Law and Enforcement” to the acronym. The term was originally a veiled reference to the United Nations or Uncle Sam. The premise was that the threat from THRUSH was so existential as to demand cooperation between the U.S. and the USSR, mortal Cold War enemies at the time. Ian Fleming, the originator of the James Bond series, was an early contributor. The original working title for the show was Ian Fleming’s Solo.

The real star of the show was the U.N.C.L.E. gun. A custom prop built around a heavily modified P38 pistol chassis, this modular carbine was the very embodiment of 1960s-era spy chic. The original U.N.C.L.E. gun was built atop an M1934 Mauser pistol. However, this gun seemed dwarfed by its accessories and jammed frequently. The producers therefore appropriated a Walther P38 from the nearby set of the TV series Combat! and went to work modifying it.

U.N.C.L.E. Tech

The new U.N.C.L.E. gun included a removable birdcage flash suppressor, a detachable skeletonized buttstock, an optical sight and a stylized barrel extension/sound suppressor. The prop masters created six copies at a cost of around $1,500 apiece ($12,644 today), though only two were complete kits. A U.S. Army Ordnance General approached the show’s producers asking to borrow one for evaluation and testing.

They converted one gun to full auto. However, once it appeared on screen that illegal machine gun earned the producers a visit from U.S. Treasury agents, the predecessors to today’s BATF. There resulted a $2,000 fine, and the matter was quietly resolved.

We thought it might be a fun exercise to build up an Information Age rendition of the original Man from U.N.C.L.E. gun. As the Sig Sauer P365 is arguably the most modular handgun on the planet, that seemed a great place to start. The end result just drips cool.


The SilencerCo Omega 45K suppressor can be used on either 9mm or .45 ACP platforms simply by swapping out the mounting piston. It is also delightfully compact while remaining exceptionally effective. The Omega 45K includes a built-in Linear Inertial Decoupler for uber-reliable operation.

The Streamlight TLR7 Sub tactical weapon light packs big light performance into a package not much larger than your thumb. The TLR7 Sub feeds off of a single CR123A battery and puts out 500 lumens of blistering white light. The ambidextrous tailcap switch is easily managed, and the thing is as rugged as Margaret Thatcher’s corset.

UNCLE gun with modern SIG P365 spy gun build.
The original Man from U.N.C.L.E. spy gun was a modular tactical carbine built around a WW2-vintage Walther P38 (top), with the SIG P365 build (bottom). (Photo by Alex Landeen)

The Trijicon RMRcc is a miniaturized version of their GI-issue RMR micro red-dot sight optimized and scaled for micro carry guns. The sight is powered by a standard 2032 battery that will yield up to four years of constant-on operation. The RMRcc sets its own brightness automatically. Fast in action and nearly indestructible, the Trijicon RMRcc is combat-grade glass.

Serious Firepower

The Sig P365 accepts a variety of stick magazines. However, for this project we wanted something a bit manlier. Promag makes two different drum magazines for this stubby little concealed carry gun. One packs 30 rounds, while the other carries 50. Constructed of rugged proprietary DuPont Zytel polymer, these drums feature full-length stamped and welded steel inserts for strength and durability. An ample loading wheel built into the front of the magazine makes it easy to charge to full capacity.

Grayguns offers a wide array of top-quality Sig accessories to include custom laser engraved polymer grip modules in gray or black featuring deep “Grayscale” texturing. This treatment not only looks freaking awesome, it also substantially enhances your grip on the gun, particularly when sweaty or terrified. They also offer a drop-in manual safety for the P365. Use it if you want, ignore it if you don’t. I like the option.

True Precision builds the custom threaded barrel. Available in nine different finishes and rocking some seriously rarefied aesthetics, True Precision barrels are match-grade accurate and dead nuts reliable. True Precision tubes come as a drop-in fit and run like a lawyer after money.

Ballistic Synergy

The end result remains bulky but svelte and looks almost too cool for words. This modular spy gun was utterly reliable with everything we fed it. It also moved fast and shot straight. With 50 rounds on tap you’ll get tired of stroking the trigger before the gun runs dry.

The Omega 45K excises most of the gun’s snap, though you’ll still want some plugs, particularly up close. The end result remains nonetheless usable within enclosed spaces without totally trashing your tactical awareness, which is the point. Combined, the Trijicon RMRcc red-dot and Streamlight TLR7 Sub bring the next best thing to night vision.

You need to make a sober assessment of how awesome you are before trying to build up your own Man from U.N.C.L.E. gun. Not just everybody can handle this much raw, unfiltered cool. Running such a beast will reliably get you dates with supermodels, cure male-pattern baldness and make even the dumpiest Midwestern accountant look just a little bit like a suave international superspy. After a little trigger time I’m feeling kind of extra amazing myself.


This article is from the October-November issue of Ballistic magazine. Grab your copy at

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