Custom Glock 17 – Gen 3

“Old habits die hard.”

That’s a nugget of wisdom you have probably heard before. Maybe it was your dad who said it, maybe it was Grandpa. Maybe it was a variation on the adage, something like “It’s hard to teach an old dog new tricks.”

Whatever the saying or setting, the meaning is clear. Trends and fads come and go, but at an individual level, like pepperoni on pizza in lieu of pineapple, traditional tastes tend to win out in the end.

For Leigh Guarnieri’s father, that traditional taste was for the venerable 1911, the legendary semiautomatic sidearm design that’s been in service for more than a century, starting with the John Browning’s original Colt M1911 in the year nineteen hundred and eleven.

Leigh himself has a different taste in sidearms, one that gravitates toward a more contemporary design. It’s a more modern platform for newer generations of shooters, but one that’s become nearly as ubiquitous as the 1911, both in private hands and riding the hips of law enforcement professionals. That would be the Austrian-made Glock.

In fact, one of the driving forces behind this gun, a customized Gen 3 Glock 17, was convincing his dad that more modern offerings could be every bit as functional and effective as his old military standby.

“The purpose of the build was to create a California-compliant pistol that’s comfortable in the hand and that could also be used for competition,” Guarnieri says. He goes on to say it was also to “convince my dad that a plastic gun could be as accurate and reliable as the 1911 he’s been shooting for as long as I can remember.”

To older generations, the word “plastic” can be a something of a loaded term. Except for the barrel, slide, and some small internal components, Glock pistols are constructed entirely from polymer.

A 1911, on the other hand, is fashioned entirely from wood and steel, and its construction makes it feel quite substantial as it sits in the hand—if not downright heavy. To someone accustomed to this inherent weightiness, it’s tempting to look down your nose at the much lighter Glock as “cheap.”

Any dedicated Glock user knows nothing could be further from the truth. Because of its more modern construction, in terms of cost any Glock is overall less expensive than virtually any 1911. And because the polymer frame is so much easier and more forgiving to work with, customization tends to be a much more straightforward proposition—even for a do-it-yourselfer.

When the project began in earnest Guarnieri tore the pistol apart and had work performed on the slide and frame simultaneously to keep the overall build time down. “I needed to get the slide finished and run some rounds through it,” Guarnieri says, “to make sure it performed as needed with lower-FPS ammo that would be used with lighter competition springs.”

The slide itself is a Zaffiri Precision ZPS.6 G34 unit crafted from 416 stainless with an RMR optic cut. According to Guarnieri, Stephen Zaffiri has augmented his background as a humble tool-and-die apprentice with an engineering degree to quickly become a name in the custom slide and barrel world.

The Cerakote scheme on the slide was laid down by Tampa Cerakote Facility, what Guarnieri bills as one of the premiere graphics applicators in the Southeast. Owner and operator (and armed forces vet) Tony Mittelstaedt applied the black Multicam pattern using Cerakote Armor Black, Sniper Gray, and Titanium with a matte finish.

The frame went to Rocket City Stippling in Huntsville where RCS owner Jeck Bardos executed a full custom re-shaping that includes an overall reduction of the grip’s rear palm “hump” and narrowing of the backstrap, removal of the finger grooves, and a double undercut, all to allow a higher and more comfortable grip on the gun.

The frame went to Arsenal Engraving & Coating (also in Alabama) for a full application of Cerakote Sniper Gray to match it up visually with the slide. Then it went back to RCS, where Bardos added his signature Gap Borders and a super-aggressive triangular grip texture with rounded index points to assist proper thumb placement. He finished it with borders that follow the lines of the Taran Tactical Innovations flared aluminum magwell.

“Jeck sits handcuffed to a Dremel and soldering iron working magic on polymer frames night and day,” Guarnieri says. “Few people know that he lives only on white rice. It’s his secret to having the stickiest grips in the business.”

The G17 went back together by the owner’s hand and he also performed his own testing and tuning. The custom slide actuates over a bead-blasted Zaffiri G34 barrel that is just a bit longer than the original to help keep gas pressure to aid in cycling Guarnieri’s intended ammo loads. Zaffiri also provided a billet extractor and stainless-steel backplate to help make servicing and cleaning the pistol easier.

On re-assembly, Guarnieri dropped in a ZEV Pro Ultimate trigger with a new stainless plunger and lightweight fluted firing pin, both of which use extra-light springs. “Combined with an 11-pound recoil spring and solid stainless guide rod led to the occasional light primer strike,” Guarnieri says. “So the factory Glock firing pin spring was added along with a Ghost, Inc. connector and spring. It hasn’t skipped a beat since.”

Another bit he added that works surprisingly well is the ZEV extended magazine release with a billet paddle. “It was surprising,” Guarnieri says. “Combined with the Taran Tactical magwell and the Taran +0 California-compliant baseplates on the ETS 10-round smoked magazines, you end up with fast and consistent changes that can be done under any conditions and at any skill level.”

Guarnieri finished the pistol off with an optics and sighting package that includes a Trijicon RM07 Type 2 RMR adjustable LED sight with 6.5 MOA red dot, AmeriGlo GL-329 3-dot front and rear green tritium sights, and an Inforce ALP Gen 3 weaponlight. He packs it to and from the range in a custom ZEV Technologies SKB case.

The real question, though, is will it all be enough to sway his old man from his old allegiance? Only time will tell, but it seems like Leigh has a pretty good jump on it. He likens the whole Glock-versus-1911 debate to another analogy, one that involves cars, of all things.

He’s unofficially nicknamed his pistol the “Hyundai.” Hyundais were cars that were always very functional and reliable, but until recently weren’t all that sexy. Historically, a Hyundai wasn’t necessarily something one aspired to owning. That’s all changed quite a bit in the last decade or so with the introduction of cars like the performance-oriented Genesis Coupe and the super-lux Equus.

The same might be said of the burgeoning and ever-expanding custom market for Glock, a movement that’s taken the high reliability and functionality of the Glock platform and turned it into something else entirely. A market that has, for all intents and purposes, transcended the Austrian-made pistol.

And whether he’s able to sway allegiances or not, Guarnieri has to give his father props for his baptism in the world of enthusiast shooting to begin with. Leigh is appreciative of “the years of weapons training and 43 years of doing ‘that Dad thing.”

“And I can’t forget Mom for lying to Dad about what these builds actually cost,” he adds.

Guarnieri also would like to give a nod to his boss at Tactic Enterprise, his place of employment. “For all the support and unrelenting abuse of the RSR account,” he says. “Oh, and letting me stop production and use the million-dollar Mazak lathe to make trigger pins that probably cost $2 on eBay.” 

 Text by Roland Wilkes and images by Jerry Tsai

Leigh Guarnieri’s custom
Glock G17 Gen 3


Caliber: 9mm

Length: Tk in.

Barrel: Zaffiri Precision G34 threadless

Weight w/o Magazine: TK lb, TK oz.

Coating: Cerakote by Tampa Cerakote Facility (slide), Asenal Engraving & Coating (frame)

Slidework: Zaffiri Precision ZPS.6 G34

Framework: Rocket City Stippling custom package

Featured Accessories:

Sights: AmeriGlo GL-329 3-dot front and rear green tritium w/ white outline

Optic: Trijicon RM07 Type 2 RMR adjustable LED sight

Magazine: ETS Glock 17 9mm Limited 10-round

Case: ZEV Technologies SKB

Parts & Accessories:

ZEV Technologies Pro flat-face trigger kit, ZEV Technologies Small Skeletonized V4 Sriker, ZEV Technologies Extended Mag Release, ZEV Technologies Stainles Steel Extractor, Taran Tactical Competition Magwell, Glockstore Stainless Steel Competition Recoil Spring, Ghost Inc. Edge Complete Trigger Kit, Zaffiri Precision RMR cover plate, Zaffiri Precision Stainless Back Plate, Inforce ALP Gen 3 weaponlight, Tactic Enterprise custom stainless steel pins, Glockstore Stainless Solid Rod Guide, 11-lb spring, Extended Slide Stop and Slide Release

About the Owner

Name: Leigh Guarnieri
Social: IG @ lguarnieri; FB: Leigh Guarnieri
Occupation: Vice President at Tactic Enterprise
Special Thanks: Leigh Guarnieri Sr., Dan Donovan

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