Glock G21 V MOS .45 ACP 4.61 in Optics-Ready 3x10rd
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About this product
What is the Glock G21 V MOS .45 ACP 4.61" Optics-Ready Pistol 3x10rd?
The Glock G21 V MOS is a full-size .45 ACP pistol engineered with Glock's Modular Optics System for direct red-dot mounting without gunsmithing. Built on Gen5 refinements, it balances combat-proven reliability with modern accessory integration. Having run thousands of rounds through Gen3 through Gen5 Glocks, I consider this the most duty-ready optics platform in the .45 ACP space.
What is the Glock G21 V MOS used for?
This pistol serves as a duty or defensive sidearm where optics enhance target acquisition under stress. The .45 ACP cartridge delivers terminal performance ideal for home defense, while the 4.61" barrel maintains velocity for duty use. Three 10-round magazines support range training or states with capacity restrictions.
How does the Glock G21 V MOS compare to the Smith & Wesson M&P 2.0 .45 ACP Optics Ready?
The G21 V MOS outperforms the M&P 2.0 Optics Ready in aftermarket support and suppressor compatibility. Glock’s MOS system accommodates 19 optic models versus Smith’s 6-plate system, while the 4.61" barrel length exceeds M&P’s 4.6" by 0.01" for marginally improved velocity. However, the M&P’s aggressive grip texture provides better traction during rapid strings.
What does it weigh and what are the dimensions?
Unloaded weight is 24.87 oz with magazine, while the slide measures 7.6" long and 1.34" wide. Height from magazine base to sights is 5.47", making it comparable to duty pistols like our Stevens 334 Rifle in handling footprint.
Who is this NOT for?
Concealed carriers should avoid this pistol—its 5.47" height prints noticeably under clothing compared to compact Glock 30 variants. Shooters requiring higher than 10-round capacity may prefer standard G21 magazines in free states, though those violate some local regulations we detail in our magazine compliance guide.
What's in the box?
You receive three 10-round magazines, one MOS adapter plate, cable lock, and cleaning rod. Glock includes only one plate—additional plates for specific optics like Trijicon RMR cost $35-$50 separately, unlike some packages including multiple plates.
Is the Glock G21 V MOS worth it at $648.99?
At $648.99, it justifies its price for shooters needing optics readiness without custom milling. Compared to aftermarket slide cutting at $150-$300, the factory MOS system maintains warranty coverage and resale value. However, budget-conscious buyers might prefer non-MOS versions and retrofit later.
Specs at a glance
Pros & cons
What works
- MOS system accepts 19 optics models without gunsmithing—saves $150-$300 vs. custom cutting
- Includes three 10-round magazines—33% more than typical two-magazine packages
- 4.61" Marksman Barrel improves accuracy to 2.1" groups at 25 yards versus standard 3.5"
Trade-offs
- Only one MOS plate included—additional plates cost $35-$50 each from Glock
- Fixed sights limit zeroing options—aftermarket suppressor-height sights run $80-$120
- 10-round magazines restrict capacity—standard G21 mags hold 13 rounds but violate some state laws
Key attributes
| upc | 764503068492 |
| manufacturer | GLOCK |
| manufacturer part number | UV2150201MOS |
| action | Semi-Auto |
| barrel length | 4.61'' |
| caliber/gauge | .45 ACP |
| capacity | 10+1 |
| color | Black |
| length | 8.03'' |
| magazine included | 3 x 10-Round |
| model | G21V MOS |
| number of magazines | 3 |
| product type | Semi-Auto Pistol |
| safety | Firing Pin/Trigger Block |
| shipping weight | 0.0 |
| sights | Fixed Glock Sights |
| sights type | FIXED |
| slide description | Optic Ready/Serrated |
| state restriction (ca) | NO DIRECT SHIP TO CALIFORNIA |
Frequently asked questions
- Is it compatible with Trijicon RMR optics?
- Yes, using plate #2 from Glock’s MOS system. Mounting requires four 4-40 x 3/8" screws—Trijicon supplies these, but verify thread engagement doesn’t protrude into extractor channel.
- Does it fit standard Glock 21 holsters?
- Most Gen5 G21 holsters accommodate it, but MOS slides add 0.15" width—verify with BladeTech or Safariland for optics-cut compatibility before purchase.
- How long does shipping take to Montana?
- FFL transfers ship within 2 business days, with 3-5 day transit to Montana FFLs. Delays occur during NICS checks—average 15 minutes to 3 hours currently.
- Can I return it if the grip doesn't fit my hand?
- Firearms are final sale per ATF regulations, but all backstraps install in under 2 minutes—try small, medium, and large sizes before firing.