Glock 43X MOS Review: Optics-Ready EDC Pistol Tested

The Glock 43X MOS stands as one of the most popular concealed carry pistols on the market today. This optics-ready 9mm combines Glock's proven reliability with a slim profile that makes it easy to carry all day. The Glock 43X MOS delivers 10+1 rounds of 9mm ammunition in a package that measures just 1.1 inches wide, making it an excellent choice for everyday carry while offering the ability to mount a red dot sight for improved accuracy.

What sets the 43X MOS apart as an optics-ready carry gun is its balance of size and shootability. Unlike smaller micro pistols that can be difficult to control, the 43X MOS gives you a full grip and a 3.41-inch barrel. This means you get better accuracy and recoil management without sacrificing concealability.

The MOS system opens up options for mounting various red dot sights without needing custom slide work. This feature has made the 43X MOS a favorite among shooters who want the precision advantage of an optic on their carry gun. Whether you're new to concealed carry or looking to upgrade your current setup, understanding what this pistol offers will help you make an informed decision.

Key Takeaways

• The Glock 43X MOS is a slim 9mm pistol designed specifically for concealed carry with factory optics-ready capability

• It holds 10+1 rounds and measures only 1.1 inches wide while maintaining excellent shootability and accuracy

• The pistol offers proven Glock reliability with extensive aftermarket support for holsters, sights, and accessories

Key Features of the Glock 43X MOS

The Glock 43X MOS builds on the standard 43X platform with factory machining for micro optics and improved slide manipulation. These updates make the pistol more adaptable for modern concealed carry needs while maintaining Glock's core design philosophy.

Modular Optic System Overview

The Modular Optic System comes with a milled slide that accepts micro red dot sights without needing custom machining. Your pistol arrives with adapter plates that allow you to mount various optic brands directly to the slide. The MOS version includes a removable cover plate that protects the mounting area when you're not running an optic.

This factory-cut design saves you money compared to sending your slide out for aftermarket milling. You get a clean, factory-finished mounting surface that maintains the slide's structural integrity. The system also sits lower than most aftermarket mounting solutions, which helps with sight picture and reduces the overall height of your setup.

RMSc Footprint and Optic Compatibility

Your Glock 43X MOS uses the Shield RMSc footprint, which has become a standard for subcompact pistols. This footprint works with popular micro red dots like the Holosun EPS Carry, Vortex Defender CCW, and Swampfox Sentinel. You can also mount the SIG ROMEO Zero and Crimson Trace CTS-1500 without modifications.

The included adapter plates let you fit optics with different mounting patterns. Most shooters find they can install their preferred optic in under 10 minutes using basic tools. The mounting screws should be properly torqued to prevent your optic from loosening during firing.

Front and Rear Slide Serrations

The pistol features front slide serrations in addition to the standard rear serrations. These cuts give you more gripping options when you need to rack the slide or perform press checks. The front serrations are especially helpful when you're wearing gloves or have wet hands.

The serrations have an aggressive texture that provides solid purchase without being uncomfortable during everyday carry. You'll find the added grip points useful during malfunction drills or when you need to chamber a round with limited hand strength. The slide stop remains small and unobtrusive to prevent accidental activation during firing.

Glock 43X MOS Specifications

The Glock 43X MOS delivers a compact 9mm package with a 10+1 capacity, 3.41-inch barrel, and slim polymer frame that measures just 1.10 inches wide. The pistol weighs approximately 18.6 ounces unloaded and stretches 6.5 inches in overall length.

Dimensions and Weight

The 43X MOS measures 6.5 inches in overall length, 5.04 inches in height, and 1.10 inches in width. This slim profile makes it one of the easiest Glock pistols to conceal for everyday carry.

You'll find the unloaded weight sits at approximately 18.6 ounces. This lightweight build reduces fatigue during all-day carry without compromising the gun's stability during shooting. The single-stack design keeps the grip narrow enough to fit comfortably in your hand while maintaining a full firing grip.

The polymer frame construction contributes to both the light weight and durability. You get Glock's proven frame design that resists impact, moisture, and temperature extremes while keeping the pistol easy to carry for extended periods.

Magazine Capacity and Caliber

The Glock 43X MOS chambers the 9mm Luger cartridge and ships with a standard 10+1 capacity. Your flush-fit magazine holds 10 rounds, plus one in the chamber for a total of 11 rounds ready to fire.

This single-stack 9mm configuration balances concealability with adequate defensive capacity. You sacrifice some rounds compared to double-stack models, but you gain significant advantages in width and comfort. Aftermarket options like Shield Arms S15 magazines can increase your capacity to 15 rounds if you prefer more ammunition on board.

Barrel and Slide Details

Your 3.41-inch barrel provides enough length for reliable accuracy at defensive distances while keeping the pistol compact. The 3.41 inches of barrel length strikes a balance between velocity retention and easy concealment.

The steel slide features Glock's nDLC finish for corrosion resistance and reduced friction. You'll notice the factory-milled MOS cut on top, which accepts micro red dot optics without requiring custom machining. The slide comes with fixed front and rear sights that co-witness with most micro optics.

Ergonomics and Controls

The Glock 43X MOS features a slim profile measuring just 1.10 inches wide with textured grips and ambidextrous controls. The pistol incorporates front slide serrations and a reversible magazine catch to accommodate different hand sizes and shooting preferences.

Grip Shape and Beavertail Design

The grip on the Glock 43X MOS uses a textured polymer frame that provides solid traction without being overly aggressive on your hands. The grip texture helps you maintain control during rapid fire or in wet conditions.

The beavertail design on this compact pistol is subtle compared to other firearms. It extends just enough to protect your hand from slide bite during recoil. The grip angle sits at the standard Glock 22-degree measurement, which promotes natural pointing for most shooters.

The slim width of 1.10 inches makes the pistol comfortable for concealed carry. Your hand wraps around the grip easily even if you have smaller hands. The ergonomic grip angle helps with natural pointing and shooting.

Magazine Release and Catch

The magazine release button sits in the standard Glock position on the left side of the frame behind the trigger guard. You can press it easily with your thumb without adjusting your grip.

The reversible magazine catch allows left-handed shooters to switch the button to the right side of the frame. You need basic tools to make this change.

The button has a low profile that prevents accidental magazine drops during concealed carry. You need to apply deliberate pressure to release the magazine, which adds reliability when carrying this compact pistol daily.

Slide Release and Stop

The slide stop lever sits on the left side of the frame above the trigger. It functions as both a slide release and slide lock when the magazine is empty.

You can manipulate the slide stop with your thumb to drop the slide on a fresh magazine. The lever size is small, which is typical for Glock pistols. Some shooters prefer to use the sling-shot method instead by pulling back on the slide.

The front slide serrations give you additional grip points for racking the slide. These serrations work well for press checks and malfunction clearances. The Glock trigger maintains the standard Safe Action system with a trigger safety in the center.

Range Performance and Reliability

The Glock 43X MOS delivers consistent performance at the range with tight groupings and zero malfunctions across multiple shooting sessions. Testing revealed strong accuracy potential and the legendary Glock reliability that has made these pistols favorites among shooters.

Shooting Experience

The shooting experience with the 43X MOS feels surprisingly manageable for a compact pistol. You'll notice the gun doesn't feel like a micro pistol in your hands despite its slim 1.1-inch width.

The recoil is mild and controllable. The grip length gives you enough purchase to maintain a solid hold during rapid fire. Your follow-up shots stay on target without excessive muzzle flip.

The trigger breaks at around 6 pounds with a smooth take-up. You get consistent reset feedback that helps with accuracy during range time. The bladed Safe Action system requires deliberate pressure but doesn't interfere with quick shooting.

Accuracy Results

The Glock Marksman Barrel (GMB) delivers excellent accuracy for a compact carry gun. You can expect groups under 2 inches at 15 yards with quality ammunition.

Testing with various loads from 115-grain FMJ to 147-grain subsonic hollow points showed consistent performance. The longer 3.41-inch barrel and extended sight radius give you an advantage over shorter micro compacts.

Your accuracy improves noticeably when adding a red dot sight to the MOS mounting system. The co-witness capability with suppressor-height sights provides backup aiming options.

Reliability Testing

Glock pistols have earned their reputation through flawless performance. The 43X MOS continues this tradition with zero feeding issues across hundreds of rounds.

The side-mounted extractor grips each case firmly for reliable ejection. The polished feed ramp guides cartridges smoothly into the chamber. Both included magazines loaded easily and fed without problems.

You can run different ammunition weights without adjustment. The gun cycles everything from light training rounds to heavy defensive loads. The nDLC coating protects against corrosion from sweat during carry while maintaining reliable function.

Concealed Carry Suitability

The Glock 43X MOS works well as a concealed carry pistol because of its slim profile and extended grip. The gun balances comfort during extended wear with enough capacity to be practical for everyday carry.

Everyday Carry Comfort

The 43X MOS measures just over an inch wide, which makes it easy to wear inside the waistband without creating noticeable bulges. Your clothing will drape naturally over the pistol in most carry positions.

The extended grip gives you a full purchase with all fingers on the frame. This matters when you carry the gun all day because you don't need to adjust your grip as much when drawing. The extra grip length does add about half an inch compared to the standard Glock 43, which can print slightly more at the bottom of the grip depending on your body type and clothing.

Weight distribution stays balanced even when you add a red dot optic to the MOS system. At around 19 ounces unloaded, the pistol sits comfortably without sagging your belt or causing pressure points during extended periods of wear.

Holster Selection and Aftermarket Support

You'll find dozens of quality IWB holster options made specifically for the 43X MOS. Most holster manufacturers include this model in their product lines because of its popularity as a modern single-stack 9mm pistol suited to concealed carry.

Popular holster styles include:

• Appendix carry holsters with wing attachments for better concealment

• Strong-side IWB holsters with adjustable cant and retention

• Hybrid holsters combining leather backing with Kydex shells

The aftermarket support extends beyond holsters to include magazine extensions, trigger upgrades, and sight options. This lets you customize your carry setup to match your specific needs. Shield Arms makes steel magazines that increase capacity to 15 rounds while maintaining the slim profile, though you should test any aftermarket magazines thoroughly before relying on them for concealed carry and EDC use.

Magazine Options and Capacity Enhancements

The Glock 43X MOS ships with a 10-round magazine capacity, but you have several options to increase your firepower. Aftermarket manufacturers offer extended magazines that can significantly boost your round count without major changes to concealability.

Standard Glock Magazines

Your Glock 43X MOS comes equipped with 10-round Glock magazines that use a single-stack design. These factory magazines are reliable and work flawlessly with the pistol's slim profile.

The standard magazine keeps your 43X easy to conceal while providing enough capacity for defensive situations. These magazines are interchangeable with the Glock 48, which shares the same magazine dimensions and design.

Factory Glock magazines are built to last and rarely cause feeding issues. They maintain the pistol's slim 1.10-inch width, which is critical for comfortable concealed carry. You can find these magazines wherever Glock parts are sold, and they typically come in black polymer construction.

Shield Arms S15 and Extended Magazines

The Shield Arms S15 Magazine is one of the most popular upgrades for your Glock 43X. This steel magazine increases your capacity from 10 to 15 rounds while maintaining a flush fit with your pistol's grip.

The S15 achieves this capacity boost through a double-stack design that fits within the same width as standard magazines. Users report thousands of rounds fired without reliability issues when using these magazines.

Other extended magazine options include the ETS 19-round magazine and smaller extensions like the Pearce+1 or Vickers+2. The ETS magazine nearly doubles your standard capacity but adds length to the grip. Smaller extensions add one or two rounds while improving your grip surface area without significantly affecting concealability.

Comparisons with Related Pistols

The Glock 43X MOS occupies a specific space between ultra-compact single-stacks and larger duty pistols. The 43X MOS holds 10+1 rounds with a 3.41-inch barrel, while competitors and Glock's own lineup offer different capacity and size trade-offs that directly affect concealment and shootability.

Glock 43 vs. Glock 43X MOS

The original G43 features a 6+1 capacity compared to the 43X's 10+1 round magazine. Both guns share the same 3.41-inch barrel and similar width measurements between 1.06 and 1.10 inches.

The key difference comes down to grip length. The 43X adds just 0.75 inches to the magazine and grip, which increases capacity by four rounds. This means the G43 remains slightly more concealable but gives up significant firepower.

The 43X weighs about 23 ounces loaded versus 20.6 ounces for the G43. The 43X MOS also adds optics-ready capability with a removable cover plate, which the standard G43 lacks entirely. If you prioritize maximum concealment over capacity, the G43 makes sense. But for most shooters, the 43X MOS offers a better balance of size and capability.

Glock 43X MOS vs. SIG P365 and Hellcat OSP

The SIG P365 holds 12+1 rounds while the Springfield Hellcat OSP carries 11+1 or 13+1 with an extended magazine. Both guns give you more ammunition in a smaller package than the Glock.

The P365 features a 3.1-inch barrel and the Hellcat OSP uses a 3-inch barrel, making them about a half-inch shorter than the 43X MOS overall. Both competitors weigh under 18 ounces unloaded, making them lighter than the Glock's 18.55 ounces.

Price becomes a factor here. The 43X MOS typically costs between $500 and $530, while the SIG and Springfield options hover around $600. The Glock's longer sight radius and slightly heavier weight help with recoil management and accuracy. You also get access to a massive aftermarket for holsters, parts, and accessories that smaller manufacturers can't match.

Glock 43X MOS vs. Glock 19 and 19X

The Glock 19 and 19X are compact service pistols rather than subcompacts. The G19 holds 15+1 rounds with a 4.02-inch barrel, while the 19X features the same capacity with a full-size G17 grip.

Both larger Glocks measure substantially wider and heavier than the 43X MOS. The G19 weighs around 23.65 ounces unloaded, and the 19X tips the scales even higher. This extra size makes them harder to conceal for everyday carry, especially during warm weather.

The 43X MOS handles and shoots like its larger G19 cousin despite the size difference. The Glock 48 sits between these models with a longer slide than the 43X but maintains the slim width. If you need maximum capacity and don't mind the bulk, the G19 or 19X works better. For concealed carry where printing is a concern, the 43X MOS provides adequate capacity in a much more concealable package.

Frequently Asked Questions

The Glock 43X MOS raises questions about reliability, optic compatibility, and how it stacks up against other carry options. Understanding the common concerns and improvements helps you make an informed decision about this popular concealed carry pistol.

What are the common issues with the latest generation of the Glock 43X?

The Glock 43X MOS has very few widespread issues, but the most common complaint centers on its 10-round capacity. When you compare it to competitors offering 12 to 15 rounds in similar-sized frames, the capacity feels limited for a modern carry gun.

Some shooters also find the factory plastic sights disappointing. They're basic and functional but lack the visibility you might want on a defensive pistol.

The RMSc optic footprint can be limiting if you want to mount certain red dots directly. You'll need adapter plates for many popular optics, which adds height and potentially creates extra failure points.

How does the Glock 43X MOS compare to previous generations in terms of features and performance?

The Glock 43X MOS includes the Glock Marksman Barrel found in Gen5 pistols, which improves accuracy over earlier models. This barrel features enhanced rifling and a target-style crown that you won't find on the original Glock 43.

You get an accessory rail on the 43X MOS that the standard Glock 43 lacks. This rail lets you mount lights like the Streamlight TLR-7 sub for defensive situations.

The optics-ready slide comes standard, saving you money on aftermarket milling. Previous generations required expensive modifications to mount red dots.

What are the notable improvements in the Glock 43X MOS over its predecessors?

The factory optics cut stands out as the biggest upgrade. You can mount micro red dots right out of the box without sending your slide to a gunsmith.

The grip length increased compared to the Glock 43, giving you a full three-finger purchase. This makes the gun easier to control and more comfortable to shoot for extended sessions.

You also benefit from the accessory rail addition. The original Glock 43 had no way to mount a weapon light, which limited its defensive capabilities in low-light situations.

What are the advantages and disadvantages of choosing a Glock 43X MOS for concealed carry?

The main advantages include proven Glock reliability and a slim 1.1-inch width that conceals easily. The optics-ready slide and accessory rail make it a capable defensive tool right from the factory.

You also get access to massive aftermarket support with countless holsters, triggers, and other modifications available. This means you can customize the gun to fit your specific needs and preferences.

The disadvantages center on capacity and optic limitations. Ten rounds falls short compared to guns like the SIG P365 or Springfield Hellcat that offer more ammunition in similar packages. The RMSc footprint also restricts your direct-mount optic choices unless you want to use adapter plates.

How has the Glock 43X MOS been received by the firearms community in recent reviews?

The firearms community views the Glock 43X MOS as a top concealed carry contender despite its capacity limitations. Reviewers consistently praise its reliability, with many reporting zero malfunctions through hundreds of rounds.

Shooters appreciate the slim profile and ease of concealment, especially during warmer weather when clothing options decrease. The gun performs well at defensive distances, keeping tight groupings within 15 to 25 yards.

Critics point out that newer competitors offer better capacity in similar or smaller packages. However, the Glock name and proven track record keep it popular among those who prioritize reliability above all else.

Can the Glock 43X MOS accommodate a wide range of optics, and how does this affect its versatility?

The Glock 43X MOS uses an RMSc footprint, which limits your direct-mounting options compared to more common footprints. You can mount optics like the Vortex Defender CCW directly, but popular choices like the Holosun EPS Carry require adapter plates.

Using adapter plates adds height to your optic mounting, which can affect your sight picture and potentially create additional points of failure. This makes the gun less versatile than models with more universal footprints.

You still have access to red dot sight compatibility that improves accuracy for everyday carry. The optics-ready design means you're not locked into iron sights, even if your choices are somewhat limited without plates.