FN 509 LS Edge 9mm Pistol: Full Review

The LS Edge 9mm pistol is FN's best multi-use 509 yet. Here's why.

July 12, 2021 By Keith Wood

The lines between handguns used for defense and competition are sometimes blurred. Lightened slides, electro-optics and features such as flared magazine wells used to be exclusive to race guns for competition. No longer. More than two decades of constant warfare, much of it at close quarters, has driven significant innovations in the firearms industry. As a result, fighting handguns have increasingly adopted those performance-based features. Custom companies may have driven the change, but major gun manufacturers are adapting as well. One of the best examples of this emerging hybrid breed of production handguns is the new FN 509 LS Edge, a pistol that’s certain to make waves.

FN is one of the oldest names in firearm manufacturing, having manufactured iconic battle-tested small arms from the P.35 to the FAL. The company created a U.S. subsidiary in the 1980s to produce M240 and M249 belt-fed machineguns under contract for the U.S. military. In 1981, FN built a manufacturing facility in Columbia, South Carolina, which led to a commercial expansion that included handguns.

FN 509 LS Edge pistol (Michael Anschuetz / FN America LLC photo)

Since appearing on the July 2017 cover of Guns & Ammo, FN’s flagship handgun line has been the 509. FN developed the polymer-framed, striker-fired semiauto into a family that include full-size, compact, tactical and midsize versions. Until the 2021 launch of the 509 LS Edge, the one pistol missing from FN’s lineup was a gun suited equally for duty use or competitive pursuits. The 509 LS Edge straddles that fence. With a list price of $1,499, the LS Edge commands a premium, but as I found out through recent training, many believe it’s worth it. The 509 LS Edge rivals the SIG Sauer XFive Legion ($999), HK VP9L OR ($949), and Walther Q5 Match Steel Frame Pro ($1,649).

Firearm engineers and product managers are not typically experienced endusers of the guns they are designing. To FN’s credit, they relied on input from armed professionals to develop and refine the features of the 509 LS Edge. Alongside the engineers, for example, FN hired one warrior and one competitor: U.S. Army MSgt. Tim Kennedy and Champion Dave Sevigny.

A suppressor-height, fiber-optic front sight paired with a no-dot black rear sight compliment FN’s trademarked “Low-Profile Optics-Mounting System.” (Michael Anschuetz / FN America LLC photo)

Kennedy is a retired professional Mixed Martial Arts (MMA) fighter who joined the Army on 9/11. His path took him into Special Forces, which resulted in numerous combat deployments as part of the elite Crisis Response Force (CRF). Kennedy knows what it means to trust your life to a firearm.

Sevigny comes from another perspective altogether. He is one of the most successful competitive shooters ever, with 253 major championship wins including 13 USPSA national titles. Some might call him the “Tom Brady of handgun shooting.”

(Michael Anschuetz / FN America LLC photo)

FN’s engineers spent two years developing the 509 LS Edge with constant input from Kennedy and Sevigny. Their unique perspectives meant that the design was balanced and didn’t become too tactical or too racy. The result is an impressive handgun that is immediately recognizable as something different.

The first feature a person sees on the 509 LS Edge is the long, scalloped slide with several milling cuts. The slide’s Graphite-color Physical Vapor Deposition (PVD) finish contrasts slightly with the black polymer frame, and it’s a handsome look. The LS Edge has a 5-inch barrel and an overall length of 8.2 inches. This puts it comfortably between the Glock 17 MOS and G34 MOS ($720) in terms of size.

Themes of speed and control are evident throughout the 509 LS Edge to include an oversized, knurled magazine-release button, tactile texturing and interchangeable backstraps. (Michael Anschuetz / FN America LLC photo)

Because of deadlines and limited resources, gunwriters seldom get to put as many rounds through a firearm as they would like. This was not the case with me and the 509 LS Edge. I was one of a handful of individuals who traveled to the Georgia coast to meet with Kennedy, Sevigny and the rest of the FN team for an extensive hands-on experience. After a product briefing, Kennedy and Sevigny ran the group through a fast-paced live-fire training program using the 509 LS Edge. We put thousands of rounds downrange during a series of instructor-led drills.

It became apparent during training that, though Kennedy and Sevigny come from very different backgrounds, their philosophies are almost identical. The same shooting efficiency, speed and precision that kept Kennedy alive on the battlefield put victory in Sevigny’s hands. Similarly, the lines have merged between tactical and defensive mindset civilians, and so are the tools that they seek.

Unusual for production defensive pistols, the 509 LS Edge comes standard with a flared, anodized aluminum funnel for competition-like magazine changes. (Michael Anschuetz / FN America LLC photo)

Kennedy is fond of saying “Never enter a fair gunfight,” and, as a competitor, Sevigny looks for every advantage he can find. Among those advantages are the increasingly widespread use of pistol-mounted red-dot sights. Optics can eliminate the challenges of traditional iron sights by putting the aiming point and target on the same visual plane. Though they can take some getting used to, they are often faster and more precise than traditional iron sights. Many shooters don’t realize that FN has been a market leader in this area. Remember the optic-ready FNP-45 Tactical introduced in 2006?

To accommodate the use of an optic, FN developed a low-profile mounting system for the 509. To facilitate mounting, a steel sight plate is removed from the top of the slide. A series of adapter plates and fasteners are neatly organized and included in a pack as a standard feature. This kit allows for the mounting of all the popular handgun optics with one exception: the Aimpoint ACRO P-1. Red dots mounted to the 509 LS Edge co-witness with the iron sights, meaning that they are both aligned with one another when zeroed. Visually, the red dot sits on top of the front sight blade. Shooters unaccustomed to shooting a pistol given a red-dot optic, can simply index the pistol with the sights on target. Viola! If you come close to lining up the iron sights, the red dot appears. I’m a relative newcomer to using optics on pistols, but I quickly adapted. I found it both fast and precise.

Some will question the reliability and durability of an electronic sight for defensive use, and I, too, was skeptical. High-quality optics such as Leupold’s DeltaPoint Pro that I mounted for this evaluation have proven to be reliable, and improvements to battery life come every year. Even if a sight does go down, or the battery quits, all is not lost. If the dot were to disappear, you still see the iron sights. And they are already on target, so the transition is seamless. Using the 509’s irons alone, Kennedy commented that I shot faster than with the red dot. No doubt this is due to my lifelong familiarity with them.

The iron sights on the LS Edge are excellent, with a drift-adjustable steel notch rear and a serrated front blade with a green fiber-optic installed. The front sight post is .040-inch wide, and the rear notch measures .150 inch. The 509 LS Edge’s sight radius is a long 6.7 inches.

Four lightening slots on each side of the long slide reveals the 5-inch, hammer-forged barrel. At the muzzle, the barrel reveals a target-like crown to protect its accuracy potential. (Michael Anschuetz / FN America LLC photo)

The ability to make rapid and accurate follow-up shots is always desired in a fight. The slide cuts on the 509 LS Edge are aggressive-looking and pass through so that the barrel is visible. Lightening the slide in this manner offered excellent gripping surface. Plus, a lighter slide means that there is less reciprocating mass, which reduces muzzle flip. The grip is textured extensively and offers plenty of grip without being too abrasive. Also, two additional interchangeable backstraps are provided that will accommodate a variety of hand sizes without permanent alteration to the frame.

A Picatinny rail on the dustcover accepts popular accessories. The frame is also cut for a high grip on the pistol, which is a huge benefit when you need to shoot fast, controllably. A removable aluminum magazine well accepts speed reloads without adding significantly to the pistol’s dimensions, either.

There is one final piece to this gun’s performance puzzle: the trigger! As great as today’s striker-fired handguns can be, many of their triggers offer nothing to brag about. For this reason, aftermarket drop-in ignition parts are increasingly common. However, quality control and safety can be suspect, and void the gun’s warranty, so a replacement isn’t always an option. FN engineers thankfully tuned the LS Edge for high-performance. A newly-designed striker reduced the LS Edge’s trigger pull by 1 1/2 pounds when compared to the other 509s. Though the trigger on G&A’s sample measured 51/4 pounds, production triggers will likely fall in the 4- to 5-pound range. Worth noting, the flat-faced trigger did have some take-up, which met the wall at its 90-degree vertical position. This made for a comfortable break and a short reset. Kennedy and Sevigny pushed us to shoot fast during our training and the 509 LS Edge’s unit helped me reach my potential.

The remainder of the features and controls are what you’d expect from this category. A slide-mounted extractor doubles as a loaded-chamber indicator, a fixed steel ejector and an ambidextrous slide stop are all present. The barrel’s feed ramp and supported chamber are polished to maximize feeding, too, and the steel magazine release is oversized and checkered. It was easy to change mags without needing to shift my grip. Further, the takedown lever made for a nice gas pedal.

FN tapped champion Dave Sevigny (sevignyperformance.com) to ensure the 509 LS Edge meets the needs of serious competitors. (Michael Anschuetz / FN America LLC photo)

The 509 LS Edge feeds from 17-round steel magazines equipped with polymer followers, and durable, anodized, aluminum baseplates. The magazine body tapers upward at the mouth, which provides a single feeding plane and a shape that readily finds its way into the frame. The bright orange follower helped me to determine quickly whether one of the three provided magazines was loaded or not with the slide locked to the rear. If you end up owning one, know that the LS Edge accepts the 24-round mags available from FN for $60 apiece. (They’re so worth it.)

Thanks to its well-thought-out design, I quickly became a fan of the 509 LS Edge. Hours after beginning training, I was shooting it with greater speed and accuracy than handguns that I have shot for years. (Thanks are, no doubt, due to the nearly one-on-one coaching from two outstanding instructors.) It deserves mentioning that out of something like 8,000 collective rounds shot during the training session, plus the hundreds of rounds that I fired back at home, zero malfunctions occurred.

The 509 LS Edge pairs FN’s battle-proven design with Tim Kennedy’s (sheepdogresponse.com) fighting know-how for maximum advantage. (Michael Anschuetz / FN America LLC photo)

True to its design, the 509 LS Edge will be equally at home among defense-minded and competitive shooters. Sevigny plans to use the 509 LS Edge as his new match gun, in fact, which will surely influence others to follow suit. Judging by my read of the rule book, the 509 LS Edge will be eligible for USPSA Limited, Limited 10 as well as the Production and Carry Optics divisions once the requisite production of 500 guns has been met.

Whether you are a competitive shooter, someone who carries a large firearm for duty or self-protection, or perhaps someone who enjoys one-hole clusters on target, the FN 509 LS Edge has a lot to offer. This is a well-designed and well-executed handgun that will be emulated by others. Just wait and see. It is exciting to witness a company as FN, with so much rich history, continue to influence the industry.