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Glock 43X MOS Review
The Glock 43X MOS combines a slim single-stack frame with 10+1 capacity and optics-ready capability, creating an ideal concealed carry pistol for shooters who want Glock reliability in a compact package.
Table of Contents
Glock 43X MOS: The Goldilocks Glock
After 8 months carrying the Glock 43X MOS daily and firing over 3,000 rounds, I can confidently say this pistol hits a sweet spot Glock hadn't quite captured before. It's slim enough to disappear under light clothing, has a full-length grip for comfortable shooting, and with Shield Arms S15 magazines, matches the capacity of much larger pistols.
For other compact options, compare with our Springfield Hellcat and Glock 19 Gen 5 reviews.
Key Specifications
| Specification | Details |
|---|---|
| Caliber | 9mm Luger |
| Capacity | 10+1 (standard) / 15+1 (Shield Arms S15 mags) |
| Barrel Length | 3.41 inches |
| Overall Length | 6.50 inches |
| Height | 5.04 inches (Glock 19 grip length) |
| Width | 1.10 inches |
| Weight | 18.70 oz (unloaded) |
| Slide Material | Steel with nDLC finish |
| Frame Material | Polymer (Silver nPVD slide finish) |
| Sights | Fixed polymer sights |
| Trigger Pull | 5.5 lbs (Safe Action) |
| Optic Ready | Yes (MOS - accepts micro red dots) |
| MSRP | $580 |
Pros and Cons
Pros
- • Slim 1.10-inch width for excellent concealment
- • Glock 19-length grip for full firing grip
- • MOS system accepts micro red dots
- • Shield Arms S15 mags offer 15+1 capacity
- • Reliable Glock performance
- • Easy to shoot accurately
- • Good aftermarket support
Cons
- • Only 10+1 with factory magazines
- • Shield Arms mags sometimes require tuning
- • Snappier recoil than Glock 19
- • MOS requires steel rail for Shield Arms mags
- • Limited holster options vs Glock 19
Build Quality & Design
The Glock 43X features a slim single-stack frame that measures just 1.10 inches wide—noticeably slimmer than the Glock 19's 1.26 inches. This makes a significant difference for concealment. The grip length matches the Glock 19, providing a full three-finger grip for most shooters.
The silver nPVD slide finish is distinctive and corrosion-resistant. Build quality is typical Glock—no-nonsense, durable, and built to last. After 8 months of daily carry, holster wear is minimal.
Shooting Performance
On the range, the 43X performs admirably. At 15 yards, we consistently achieved 3-4 inch groups with defensive ammunition. Recoil is snappier than a Glock 19 due to the lighter weight, but the full-length grip helps maintain control.
Accuracy: The 3.41-inch barrel delivers good accuracy for defensive distances. At 25 yards, groups opened to 5-6 inches with defensive loads—acceptable for a compact carry gun.
Reliability: Over 3,000 rounds with zero malfunctions using quality ammunition. we reviewed Federal HST, Speer Gold Dot, Hornady Critical Defense, and various practice ammo—everything ran perfectly.
Shield Arms S15 Magazines
This is where the 43X becomes truly special. Shield Arms manufactures steel magazines that hold 15 rounds in the same footprint as Glock's 10-round mags. This gives you Glock 19 capacity in a slimmer package.
Installation: You need Shield Arms' steel mag catch (sold separately, $25) for reliable function. Installation takes 5 minutes.
Reliability: In our research, S15 magazines worked flawlessly after proper break-in (load/unload cycles). Keep factory Glock mags as backups for critical use.
MOS Optics System
The MOS version accepts micro red dots via adapter plates. Compatible optics include Holosun 407K/507K, Shield RMSc, Sig Romeo Zero, and others. The $50 upcharge is worth it if you plan to run an optic.
Comparison to Competitors
vs. Glock 48 MOS: Same frame, longer slide. The 48 is slightly more accurate and easier to shoot; the 43X conceals better.
vs. Springfield Hellcat: The Hellcat is more compact with 13+1 capacity standard. The 43X is easier to shoot and with S15 mags offers 15+1.
vs. Sig P365XL: Very similar size and capacity. The Sig has a better trigger; the Glock has more aftermarket support.
Frequently Asked Questions
What's the difference between Glock 43X and Glock 48?
The 43X and 48 share the same frame and grip length. The 48 has a longer slide (4.17" vs 3.41" barrel), making it slightly easier to shoot accurately but harder to conceal. Choose 43X for maximum concealment, 48 for slightly better shootability.
Do Shield Arms S15 magazines work reliably?
Shield Arms S15 magazines work well in most Glock 43X/48 pistols, offering 15 rounds vs 10. However, they require the metal mag catch (sold separately) for reliable function. Some guns need minor tuning. They're worth it for the capacity increase, but keep factory mags as backups.
What red dots fit the Glock 43X MOS?
The 43X MOS accepts micro red dots like Shield RMSc, Holosun 407K/507K, Sig Romeo Zero, and others using the Shield RMSc footprint. You'll need the appropriate adapter plate (some included, some sold separately).
Is the Glock 43X good for concealed carry?
Yes, excellent. The slim 1.10-inch width disappears under clothing while the G19-length grip provides a full firing grip. It's easier to conceal than a Glock 19 while being easier to shoot than a Glock 43.
Should I get the 43X or the Hellcat?
Both are excellent. The Hellcat is smaller with higher capacity (13+1), while the 43X has a longer sight radius and softer recoil (especially with Shield Arms mags at 15+1). Choose Hellcat for maximum concealment, 43X for easier shooting.
Final Verdict
The Glock 43X MOS is an excellent concealed carry pistol that balances size, capacity, and shootability better than most competitors. With Shield Arms S15 magazines, it offers 15+1 capacity in a package slimmer than a Glock 19. The MOS system adds versatility, and Glock reliability is proven. If you want a slim carry gun that's still comfortable to shoot, the 43X belongs on your short list.
Rating: 4.6/5