# Glock G21 Gen 4 .45 ACP - Ergonomic Power & Precision Pistol

**Brand:** Glock
**Category:** Full Size Handguns
**Caliber:** .45 ACP

## Specifications

- **Caliber:** .45 ACP
- **Barrel Length:** 4.6"
- **Capacity:** 13 rounds
- **Finish:** Black
- **Weight:** 29.3 oz
- **Overall Length:** 8.03"
- **UPC:** 764503102035
- **SKU:** UCDSUL6Y7

## Description

The Glock G21 Gen 4 is a full-sized semi-automatic chambered in .45 ACP. It has a 4.6-inch barrel, 8.03-inch overall length, and 5.47-inch height. Weight is 1.83 lbs (29.3 oz). The polymer frame pairs with a forged steel slide finished in black. Capacity is 13 rounds, with one additional in the chamber. Action is double action; safety systems include trigger, firing pin, and drop safeties, all passive.

### Key Specifications
- **Manufacturer:** Glock
- **Model:** G21
- **Series:** Gen 4
- **Caliber:** .45 ACP
- **Barrel Length:** 4.6 inches
- **Total Length:** 8.03 inches
- **Height:** 5.47 inches
- **Weight:** 1.83 lbs (29.3 oz)
- **Capacity:** 13 rounds
- **Action Type:** Double Action
- **Frame Material:** Polymer
- **Slide Material:** Forged Steel
- **Safety Features:** Trigger/Firing Pin/Drop Safety

### Features

The Gen 4 frame added interchangeable backstraps, which helps the G21 fit a wider range of hand sizes than the fixed Gen 3 grip. The textured polymer holds up well in varied conditions. Fixed sights give quick target acquisition without the complexity of adjustable options. The three-safety system is passive throughout. Trigger, firing pin, and drop safeties all work without any external lever or switch to remember.

The black steel slide finish and polymer frame resist wear during regular use.

### Usage

Home defense is where the G21 Gen 4 is most commonly deployed. The .45 ACP caliber and 13+1 capacity give it stopping power and reasonable capacity together. At the range it handles well, with the full-size frame absorbing recoil enough for sustained sessions. Despite the full-size classification (4.6-inch barrel, 8.03-inch length), some shooters do carry it concealed; most find it works better in an OWB or duty rig.

## What Customers Say

*AI-generated insights from customer reviews*

Feedback on the G21 Gen 4 is generally positive, with reliability and accuracy coming up most often. Owners report consistent function across varied conditions and ammunition types, which is the baseline expectation for Glock at this price point. And it holds up.

The interchangeable backstraps get specific mentions as an improvement over Gen 3. The customizable grip fit translates into better control and more consistent accuracy, particularly for shooters with smaller hands who previously found the G21 frame too thick.

The .45 ACP caliber is a draw for those who prioritize stopping power for personal defense. Most shooters find recoil manageable in the full-size frame, though those coming from 9mm pistols note more snap in rapid fire. Size and weight are the repeated downsides. At 1.83 lbs and full-size dimensions, it's not an easy concealed carry option, and some owners end up relegating it to home defense or range use.

The factory trigger gets split reviews. Some find it consistent and acceptable; others describe the pull as heavier than preferred. The aftermarket covers this well. Aesthetics are pure function-first Glock, no argument there, though a small segment of shooters wishes for more design variety.

## Pricing

**2 offers available**

| Vendor | Price |
|--------|-------|
| Guns Com | $499.99 |
| Gunbuyer Com | $552.87 |

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*Data from [GunsNation](https://gunsnation.com)*