
Magpul Accessories
Magpul PMAG 20 AR 300 B Gen M3 Rifle Magazine 300 AAC BLK 20/rd
Product Details
The PMAG 20 AR 300 B GEN M3 is a purpose-built magazine for rifles chambered in .300 Blackout (300 BLK). Similar in every way to our PMAG 30 AR 300 B the PMAG 20 is more compact for increased maneuverability and creates a more concealable package for use in small format firearms.
Since its inception 300 BLK shooters have had to use a magazine designed for another cartridge limiting that round’s ultimate performance and compatibility. One of the key features of 300 BLK in the past has been its compatibility with 5.56x45mm magazines. However even with moderate success with that particular magazine it is a compromise to do so with reliability and safety both being at risk.
In addition to the performance gained by a dedicated mag the PMAG 20 AR 300 B also offers a safer way to feed your 300 BLK rifle. When using 5.56x45mm mags the potential to chamber and fire a 300 BLK round in a 5.56x45mm rifle with catastrophic results requires diligent ammunition management by the shooter. The PMAG 20 AR 300 B’s distinct ribbed design and smoother upper-half texture provides the shooter a distinct visual and tactile difference from any other PMAG to mitigate dangerous cross-loading issues.
Along with optimized 300 BLK performance the PMAG 20 incorporates all of our GEN M3 features including our next-generation impact and crush resistant polymer aggressive front and rear texture an easily removable slim floor plate a paint pen dot matrix for marking and identification and a dust/impact cover.
Made in the USA.
Brand: Magpul Accessories | CA Prop 65: Yes | Compliance Magazine Type: Rifle Magazine | Magazine Caliber: .300 Blackout | Magazine Capacity: 20 rds | Magazine Finish: Black Polymer | Package Quantity: 1 | Weapon Mfg: AR-15/M-16 | Weapon Mfg Model: AR-15 UPC: 840815132233Specifications
| Brand | Magpul Accessories |
|---|---|
| UPC | 840815132233 |
| Caliber | .300 Blackout |
| Color / Finish | Black |
| Part Type | Magazine |
| Weight | 0.295 lb |
| Condition | New |
Buying this item
- Does the Magpul PMAG 20 AR 300 B Gen M3 Rifle Magazine 300 AAC BLK 20/rd ship free?
- Orders over $250 ship free within the US; smaller orders ship for a flat $9.99. Local pickup in Rocky Mount, NC 27803 is also available.
- Is the Magpul PMAG 20 AR 300 B Gen M3 Rifle Magazine 300 AAC BLK 20/rd in stock?
- Yes — live distributor inventory shows it in stock and it ships or is ready for pickup within 1–3 business days.
- What is the return policy?
- Non-firearm items may be returned within 30 days (a restocking fee of up to 15% applies if the packaging was opened). Firearms and ammunition are final sale once transferred, per federal law.
All firearm sales require background checks and compliance with federal, state, and local laws. You must be 21+ for handguns/stripped receivers and 18+ for long guns.
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