Glock 37 Review – The Overlooked .45 GAP Powerhouse

The Glock 37 is a semi-automatic, striker-fired pistol chambered in .45 GAP (Glock Auto Pistol) — a cartridge engineered by Glock to deliver .45 ACP performance in a 9mm-sized frame.

Designed for professionals who wanted .45-caliber stopping power without the bulk, the G37 balances strength, ergonomics, and control. Featuring a 4.49-inch barrel, 10-round magazine, and Glock’s Safe Action® System, it provides reliability and power in a slightly more compact, lighter platform than the Glock 21.

Though the .45 GAP never gained mainstream traction, the Glock 37 remains a uniquely capable pistol for shooters seeking a blend of high-caliber impact, consistent accuracy, and proven durability in a duty-size handgun.

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What Makes the Glock 37 a Unique .45 Caliber Pistol?

The Glock 37 stands apart as Glock’s bold attempt to innovate the .45-caliber handgun market. Introduced in 2003, it was the debut pistol chambered for .45 GAP — a proprietary round developed in partnership with Speer to replicate the ballistic performance of .45 ACP while fitting inside a standard 9mm Glock frame.

The result is a compact, full-power pistol that feels like a Glock 17 in the hand but delivers the punch of a .45. While the .45 GAP didn’t become as widespread as Glock hoped, the G37 earned a following among law enforcement agencies (notably in Florida, New York, and Georgia) and enthusiasts seeking .45-caliber performance without large-frame bulk.

Manufacturer Legacy

Glock GmbH — founded in Austria by Gaston Glock — has become synonymous with polymer reliability, simplicity, and global adoption. The company’s innovation history includes introducing the world’s first successful polymer-framed handgun, revolutionizing the firearms market in the 1980s.

The Glock 37 represents Glock’s pursuit of engineering optimization, proving that caliber and ergonomics could coexist in a balanced form. It was part of Glock’s effort to make high-caliber performance accessible to those with smaller hand sizes or those wanting the controllability of a 9mm frame.

Intended Market and Purpose

The G37 was created for law enforcement, duty use, and defensive carry. It’s meant for shooters who value stopping power and accuracy but don’t want the larger grip and recoil associated with full-frame .45 ACP pistols like the Glock 21.

What Are the Glock 37 Specifications?

Core Technical Details

• Caliber: .45 GAP (Glock Auto Pistol)

• Barrel Length: 4.49 inches (114 mm)

• Overall Length: 8.03 inches (204 mm)

• Height (with magazine): 5.47 inches (139 mm)

• Width: 1.30 inches (33 mm)

• Unloaded Weight: 26.1 oz (740 g)

• Loaded Weight: 35.3 oz (1000 g)

• Magazine Capacity: 10 rounds standard; extended magazines up to 15 rounds available

• Trigger Pull: 5.5 lbs (28 N)

• Action: Safe Action® striker-fired

• Sights: Fixed polymer (white-dot front, notched rear)

Construction and Materials

• Frame: Reinforced polymer frame with steel inserts

• Slide: Hardened steel with a corrosion-resistant finish

• Barrel: Cold hammer-forged with polygonal rifling

• Recoil System: Dual spring assembly (for improved control)

• Accessory Rail: Standard Glock rail for lights or lasers

How Is the Glock 37 Built for Reliability and Durability?

Frame and Slide Design

The G37 maintains Glock’s legendary durability and simplicity. Its polymer frame is lightweight yet strong, resistant to sweat, moisture, and environmental wear. The steel slide features Glock’s nDLC finish, providing corrosion resistance and smooth cycling even in high round-count environments.

The pistol’s balance is excellent, thanks to its compact slide design and full-size grip frame. This makes it quicker to point and easier to control than many other .45-caliber sidearms.

Ergonomics and Grip Feel

The Glock 37 shares a similar frame profile to the Glock 17, making it comfortable for a wide range of hand sizes. The textured grip surface offers solid retention even during long range sessions or adverse conditions. Shooters with smaller hands especially appreciate that they can handle .45-caliber recoil without overstretching their grip.

Controls and Safety

The Glock 37 features the familiar Glock control setup:

• Trigger safety – prevents discharge unless deliberately pressed.

• Firing pin safety – blocks striker movement until trigger pull.

• Drop safety – ensures the firearm won’t fire when dropped.

It has a left-side magazine release, a standard slide stop, and an accessory rail compatible with tactical lights.

Optics and Accessory Compatibility

As a Gen3-based model, the G37 does not have an MOS (Modular Optic System) option. However, it supports aftermarket slide milling for red dot optics, and most users upgrade the factory sights to night or fiber-optic versions for improved visibility.

What Are the Glock 37’s Variants and Closest Comparisons?

Model Lineage and Variants

The Glock 37 launched the .45 GAP family, later joined by:

• Glock 38: Compact variant with a shorter barrel and slide.

• Glock 39: Subcompact model for concealed carry.

All three share the same .45 GAP chambering but differ in size and capacity.

Generational Notes

The Glock 37 remains a Gen3-only pistol — there are no Gen4 or Gen5 updates. While this limits features like interchangeable backstraps or ambidextrous controls, it maintains the classic Glock reliability and simplicity that Gen3 models are known for.

Comparable Firearms

• Glock 21 (.45 ACP): Larger frame, higher capacity, but bulkier grip.

• Glock 17 (9mm): Similar dimensions but lighter recoil and higher capacity.

• Smith & Wesson M&P45: Similar role but uses standard .45 ACP.

• Springfield XD .45 Compact: Slightly larger, softer shooting alternative.

The G37 occupies a rare space — offering .45 performance in a 9mm-sized gun, something few other pistols replicate successfully.

How Does the Glock 37 Perform on the Range?

Accuracy and Precision

The 4.49-inch barrel gives the G37 excellent ballistic consistency. Users frequently report 1.5- to 2-inch groups at 15 yards, with consistent accuracy extending to 25 yards. The longer sight radius and stable frame make it easier to keep rounds on target during rapid fire.

Recoil Management

Despite firing a .45-caliber round, the Glock 37’s recoil is surprisingly manageable. The slide weight, grip angle, and low bore axis help dissipate recoil energy effectively. Many shooters describe it as softer than the snappy .40 S&W impulse found in G22 or G23 models.

Reliability and Round Counts

Reliability is where the Glock 37 shines. Even with thousands of rounds fired, there are virtually no reports of malfunctions when using factory ammunition. It feeds hollow points, FMJ, and +P loads reliably. Glock’s simple design ensures consistent cycling and minimal maintenance needs.

Trigger Feel and Reset

The Glock 37’s trigger follows the traditional Glock pattern — a consistent 5.5-lb pull with a smooth uptake, clean break, and short tactile reset. It’s predictable and effective for defensive or duty applications. While not match-grade, it supports fast, accurate follow-up shots.

How Compatible Is the Glock 37 with Ammunition?

Ideal Ammunition Types

The Glock 37 performs best with 185- to 230-grain .45 GAP loads, delivering energy levels equivalent to .45 ACP in a more compact case.

Recommended Defensive Loads

• Speer Gold Dot 200gr JHP (.45 GAP) – Original factory load, excellent expansion and penetration.

• Federal Premium HST 185gr JHP – Consistent accuracy and terminal performance.

• Hornady Critical Duty 200gr FlexLock – Reliable in short-barreled pistols.

• Winchester Ranger 230gr T-Series – Proven track record for law enforcement use.

Range and Practice Ammunition

For general range use:

• Speer Lawman 200gr FMJ (.45 GAP)

• Federal American Eagle 185gr FMJ

Known Issues

The main drawback is ammunition availability. The .45 GAP is a niche cartridge, less common than 9mm or .45 ACP. Shooters may need to source ammo online or in bulk. However, those who stock up experience no performance issues or feeding inconsistencies.

How Does the Glock 37 Fit Different Use Cases?

Is the Glock 37 Suitable for Concealed Carry?

While the Glock 37 is technically compact, its full-size grip and slide make it better suited for open carry or duty roles. However, its relatively slim profile for a .45-caliber pistol makes it more manageable for concealed carry than the Glock 21.

Is the Glock 37 a Good Home Defense Option?

Yes — the .45 GAP round offers excellent stopping power, and the 10-round capacity is adequate for home defense. Add a weapon-mounted light to the rail, and you have a dependable, ready-for-anything bedside pistol.

Is the Glock 37 Competition-Ready?

While not a top-tier competition pistol, the G37’s accuracy and quick handling make it a solid performer in IDPA or USPSA divisions for shooters who prefer large-caliber power.

Is It Useful for Outdoor or Field Carry?

Yes. Its durability and weather resistance make it a reliable sidearm for outdoor defense, though ammunition logistics could be a concern in remote areas.

Is It a Professional Workhorse or Range Companion?

Both — the Glock 37 is a professional-grade pistol capable of daily service use but also enjoyable to shoot recreationally due to its manageable recoil and accuracy.

What Are the Best Holsters for the Glock 37?

The right Glock 37 holster enhances comfort, retention, and draw speed. Each holster type below is crafted from durable polymer (Boltaron) for long-lasting use and consistent fit.

Cloak Tuck 3.5 IWB Holster

A Cloak Tuck 3.5 Glock 37 holster provides secure concealment with adjustable ride height and cant, making it ideal for daily carry under clothing.

Belt Holster

A belt Glock 37 holster offers strong-side carry with stable retention and quick draw — ideal for open carry or duty use.

OWB Paddle Holster

An OWB paddle Glock 37 holster provides easy attachment and removal, perfect for range sessions or casual carry.

Swivel Drop Leg Holster

A swivel drop leg Glock 37 holster positions the gun lower on the thigh for quick access during tactical or field use.

Chest Holster

A chest Glock 37 holster keeps the pistol accessible during outdoor activities like hiking or ATV riding.

Hook & Loop Holster

A hook & loop Glock 37 holster allows mounting in vehicles, safes, or packs, offering modular placement flexibility.

What Are the Glock 37’s Pros and Cons?

Pros

• .45-caliber power in a 9mm-sized frame

• Manageable recoil and excellent balance

• High reliability and durability

• Comfortable grip for most hand sizes

• Accurate and consistent performance

• Glock simplicity and ease of maintenance

Cons

• Limited ammunition availability (.45 GAP)

• No Gen4 or Gen5 updates

• Slightly bulkier for concealed carry

• Fewer aftermarket options

• Standard sights are basic and may require upgrading

What’s the Final Verdict on the Glock 37?

Who Should Buy the Glock 37?

The Glock 37 is perfect for law enforcement professionals, collectors, and enthusiasts who want .45-caliber performance in a compact, reliable package. It’s especially appealing to those who value Glock’s engineering but prefer a more balanced grip frame than the Glock 21.

Value and Long-Term Ownership

Though limited by ammo availability, the Glock 37 is a long-term investment in quality and dependability. Its build quality and low maintenance needs make it a trusted companion for decades.

Final Recommendation

The Glock 37 may be the most underrated .45-caliber Glock ever made. It delivers big-bore performance, smooth handling, and Glock reliability — all in a frame that feels as natural as a G17. For shooters willing to commit to the .45 GAP round, it remains a powerful, practical, and collectible firearm that embodies Glock’s pursuit of innovation and precision.