Glock has built its reputation on incremental refinement rather than radical reinvention. Each new generation of the platform addresses specific criticisms from the previous one — and the jump from Gen 4 to Gen 5 is no exception. Both generations are outstanding pistols, but the Gen 5 introduced a meaningful set of improvements that make it the more capable platform for most shooters.
If you're deciding between a Gen 4 and Gen 5 Glock — whether you're buying new, shopping used, or considering an upgrade — this guide covers every difference that matters in the real world. We'll look at the mechanical changes, the ergonomic refinements, the practical carry implications, and the cases where the Gen 4 might actually be the smarter choice.
A Quick History: How Glock Evolves
Glock introduced the Gen 4 in 2010, addressing several of the most common criticisms of the Gen 3: the grip was too slippery for some shooters, the recoil spring wasn't optimally tuned for all ammunition types, and the magazine release was too small for fast reloads. The Gen 4 tackled all three with a rougher grip texture, a dual recoil spring assembly, and an enlarged, reversible magazine release.
The Gen 5 arrived in 2017, initially in the G17 and G19, and has since expanded across most of the Glock lineup. It built on the Gen 4's foundation while addressing a new set of refinements: a redesigned barrel, a flared magazine well, a new trigger mechanism housing, and the removal of the finger grooves that had divided the shooting community since the Gen 2.
Understanding what changed — and why — is the key to making the right choice for your needs.
The Finger Groove Debate: Finally Resolved
If you spend any time in Glock forums or gun shops, you'll hear about the finger grooves. The Gen 3 and Gen 4 both feature molded finger grooves on the front strap of the grip — raised ridges designed to position your fingers consistently on the grip. For shooters whose hand size and grip style align with the grooves, they feel natural and secure. For everyone else, they feel awkward and can actually degrade grip quality.
Glock listened to years of feedback and removed the finger grooves entirely on the Gen 5. The result is a smooth front strap that accommodates a wider range of hand sizes and grip styles without forcing your fingers into a predetermined position. Most shooters — particularly those with larger or smaller hands — find the Gen 5 grip more comfortable and more adaptable.
This is arguably the most universally appreciated change in the Gen 5. It's also one of the reasons the Gen 5 tends to feel better in the hand for first-time Glock shooters who haven't trained their grip around the Gen 4's grooves.
The Marksman Barrel: A Real Accuracy Improvement
The Gen 5 introduced Glock's Marksman Barrel — a redesigned barrel with an improved rifling pattern and tighter tolerances compared to the Gen 4's barrel. The Marksman Barrel uses a polygonal rifling profile that Glock claims improves accuracy and extends barrel life compared to the traditional hexagonal rifling used in earlier generations.
In practical testing, the Gen 5 barrel does produce tighter groups at distance, particularly at 25 yards and beyond. The improvement is most noticeable in precision shooting contexts — competition, long-range drills, or any situation where you're pushing the gun's accuracy limits. For defensive use at typical engagement distances of 3-15 yards, the difference is less significant, but it's a genuine improvement nonetheless.
The Marksman Barrel also features a recessed target crown — a recessed muzzle that protects the crown from damage during holstering and handling. This is a small but thoughtful detail that contributes to long-term accuracy consistency.
Flared Magazine Well: Faster Reloads Under Pressure
The Gen 5 added a subtle but functional flare to the magazine well — a slight outward taper at the bottom of the grip that guides the magazine into the gun more reliably during a reload. On the Gen 4, the magazine well has straight walls that require more precise alignment during a speed reload, particularly under stress or with gloves.
The Gen 5's flared well doesn't transform the gun into a competition race pistol, but it does make fumbled reloads less likely in high-stress situations. For defensive carry, where a reload might happen under extreme stress with degraded fine motor skills, any improvement in reload reliability is meaningful.
Competitive shooters who have trained extensively with the Gen 4 may not notice a significant difference, but new shooters and those who train less frequently will appreciate the more forgiving magazine well.
Trigger Mechanism Housing: The nDLC Finish
The Gen 5 introduced a new trigger mechanism housing (TMH) with an improved geometry that slightly changes the trigger's feel and reset. The Gen 5 trigger is generally described as having a slightly shorter reset and a cleaner break than the Gen 4, though the difference is subtle and not universally agreed upon in the shooting community.
More significantly, the Gen 5 introduced Glock's nDLC (nano Diamond-Like Carbon) finish on the barrel and slide. This finish is harder and more corrosion-resistant than the Tenifer finish used on earlier generations, providing better long-term durability in harsh environments. For carry guns that are exposed to sweat, humidity, and daily wear, the improved finish is a practical advantage.
The Gen 5 also features an ambidextrous slide stop lever — a small but meaningful addition for left-handed shooters who previously had to use the Gen 4's single-sided control. This change makes the Gen 5 a more versatile platform for a wider range of users.
Recoil Spring: Shared Improvement, Different History
The Gen 4 introduced the dual recoil spring assembly (RSA) to address reliability issues with +P ammunition and to reduce felt recoil. This was a significant improvement over the Gen 3's single recoil spring, and it carried over to the Gen 5 with further refinements.
Both the Gen 4 and Gen 5 use dual recoil spring assemblies, but the Gen 5's RSA is tuned differently and is not interchangeable with the Gen 4's. The Gen 5's spring assembly is generally considered more reliable across a wider range of ammunition types, including lighter target loads that can cause reliability issues in some Gen 4 pistols.
For most shooters running standard pressure 9mm ammunition, both generations are equally reliable. The difference becomes more apparent with lighter loads or suppressed configurations where the reduced back-pressure can affect cycling reliability.
Front Slide Serrations: A Practical Addition
The Gen 5 added front slide serrations — aggressive cuts on the front of the slide that allow you to rack the gun using a press-check grip or a forward-hand technique. The Gen 4 only has rear serrations, which limits your options for manipulating the slide.
For most defensive carry applications, rear serrations are sufficient. But for shooters who perform press checks regularly, use a forward-hand technique for malfunction clearances, or simply prefer the additional grip surface, the front serrations are a welcome addition. They also give the Gen 5 a more modern aesthetic that many shooters prefer.
What the Gen 4 Still Does Better
The Gen 5 is the more refined platform in most respects, but the Gen 4 has genuine advantages in specific contexts:
Aftermarket support: The Gen 4 has been on the market for over a decade, and the aftermarket ecosystem for Gen 4 Glocks is enormous. Trigger upgrades, barrels, slides, grip modifications, and accessories are widely available and often less expensive than Gen 5 equivalents. If you plan to heavily customize your Glock, the Gen 4 may offer more options at lower cost.
Price: Used Gen 4 Glocks are widely available at prices $100-$200 below comparable Gen 5 pistols. For budget-conscious buyers who want a reliable Glock without paying a premium for the latest generation, the Gen 4 represents excellent value. A used Gen 4 G19 in good condition is one of the best values in the defensive pistol market.
Finger grooves: This cuts both ways. Shooters who have trained extensively with the Gen 4's finger grooves and whose hand size aligns well with them may actually prefer the Gen 4 grip. The grooves provide a consistent reference point for grip placement that some shooters find beneficial for accuracy and consistency.
Familiarity: If you've trained thousands of rounds with a Gen 4, switching to a Gen 5 introduces a period of adjustment. The grip feel is different, the controls are slightly different, and muscle memory built around the Gen 4 may need to be recalibrated. For experienced Gen 4 shooters, the upgrade may not be worth the transition cost.
MOS Variants: Optics-Ready Options
Both the Gen 4 and Gen 5 are available in MOS (Modular Optic System) configurations that allow you to mount micro red dot sights directly to the slide. The Gen 5 MOS is generally considered the more refined implementation, with a wider range of compatible optics and a more secure mounting system.
If running a red dot is a priority — and for defensive carry and competition, it increasingly is — the Gen 5 MOS is the better platform. The Gen 4 MOS works well but has a more limited optics compatibility list and an older mounting system that some shooters find less secure under sustained recoil.
Which Models Are Available in Gen 5?
It's worth noting that not every Glock model is available in Gen 5. The Gen 5 lineup currently includes the G17, G19, G19X, G20, G21, G22, G26, G34, G45, and several others. Smaller models like the G43 and G43X remain in their current generation without a Gen 5 variant. If you're set on a specific model that isn't available in Gen 5, the Gen 4 (or current generation) is your only option.
Who Should Choose the Gen 4?
- Budget-conscious buyers who find a used Gen 4 at a significant discount
- Shooters who have trained extensively with Gen 4 finger grooves and prefer them
- Those who want maximum aftermarket customization options at lower cost
- Buyers looking for a specific model not yet available in Gen 5
- Shooters who already own a Gen 4 and are satisfied with its performance
Who Should Choose the Gen 5?
- First-time Glock buyers who want the most current and refined platform
- Shooters with hand sizes that don't align well with the Gen 4's finger grooves
- Those who want the Marksman Barrel's improved accuracy potential
- Left-handed shooters who benefit from the ambidextrous slide stop
- Carriers who want the improved nDLC finish for better corrosion resistance
- Anyone who plans to run a red dot and wants the best MOS implementation
Complete Your Glock Setup with the Right Holster
Whether you run a Gen 4 or Gen 5, a quality holster is essential for safe and comfortable everyday carry. At WARRIORLAND, we offer a full lineup of purpose-built Kydex holsters compatible with both generations across the most popular Glock models:
- IWB Kydex Holster — Glock 17/19/34 Gen 3-5, 22/23/31/32 Gen 3-4, 19X/44/45 — A versatile IWB holster covering the most popular Glock carry models across Gen 3 through Gen 5. Adjustable cant and retention for a fully customized carry setup.
- IWB & OWB Convertible Holster — Glock 17/19/26/34 Gen 3-5, MOS Compatible — A dual-mode holster that converts between IWB and OWB carry. Compatible with Gen 4 and Gen 5 MOS variants including G17, G19, G26, G34, G19X, G44, and G45. Optics-ready.
- Clear Polymer IWB Holster with Claw — Glock 17/19 Gen 4-5, 19X/44/45, Optics Cut — A lightweight clear polymer shell with an integrated claw attachment for reduced printing. Full optics cut for red dot compatibility. Ideal for appendix carry under a t-shirt.
- Glock 19 IWB Holster with TLR-8/TLR-8A — Gen 3-5, Optics Cut — Purpose-built for Glock 17/19 setups running a Streamlight TLR-8 or TLR-8A weapon light. Full optics cut and adjustable retention for a complete light-bearing carry setup.
- IWB Kydex Holster for Glock 19 with TLR-7/TLR-7A — Gen 3-5, Optics Cut — Designed for Glock 17/19 with a Streamlight TLR-7 or TLR-7A mounted. Optics cut, adjustable cant and retention, right-hand draw.
- IWB Kydex Holster for Glock 19 with TLR-8/TLR-8A — Gen 3-5, Optics Cut — A slim IWB option for light-bearing Glock 17/19 setups with the TLR-8 series. Full optics cut for stacked red dot and light configurations.
- Level II Retention OWB Holster — Glock 17/19 Gen 6, 22/31, Optics Cut — A duty-grade OWB holster with Level II thumb-release retention and a full optics cut. Built for open carry, duty use, or competition where security retention is required.
- OWB Holster — Glock 17/19 Gen 3-5, 22/23/31/32 Gen 3-4, 19X/44/45 with MA1 Light — An OWB holster designed for Glock setups running the MA1 Crossbow tactical light. Compatible across Gen 3-5 for the most popular Glock carry and duty models.
- Drop Leg Platform — Glock 17/19 Gen 3-5, MA1/TLR-1, Level II, Optics Cut — A full drop leg platform for Glock 17/19 with weapon light compatibility. Level II retention, adjustable leg straps, and optics cut for duty, range, or competition use.
- Glock 17/19/23/26/32 Gen 4-5, 19X/44/45 IWB Holster — Tan, Right/Left Handed — A classic tan Kydex IWB holster covering the full range of popular Gen 4 and Gen 5 Glock carry models. Ambidextrous compatibility with adjustable retention.
- Glock 17/19/23/26/32 Gen 4-5, 19X/44/45 IWB Holster — Army Green, Right/Left Handed — The same versatile IWB platform in an army green finish. Covers Gen 4 and Gen 5 Glock carry models with ambidextrous carry options.
Final Verdict
The Glock Gen 5 is the better pistol for most shooters buying new today. The removal of the finger grooves alone makes it more universally comfortable, and the Marksman Barrel, flared magazine well, ambidextrous controls, and improved finish are all meaningful upgrades that add up to a more refined carry and shooting experience.
That said, the Gen 4 is far from obsolete. It's a proven, reliable platform with an enormous aftermarket ecosystem and widely available used pricing that makes it one of the best values in the defensive pistol market. For budget-conscious buyers, Gen 4 loyalists, or shooters looking for specific models not yet available in Gen 5, the Gen 4 remains an excellent choice.
The bottom line: if you're buying new and the price difference is manageable, choose the Gen 5. If you're shopping used or already own a Gen 4 that's serving you well, there's no urgent reason to upgrade — but if you ever find yourself wanting a cleaner grip, better accuracy, or ambidextrous controls, the Gen 5 is waiting.
Either way, pair your Glock with a purpose-built Kydex holster from WARRIORLAND and you'll have a carry setup built around one of the most proven pistol platforms in history.
