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PMAG® 30 AR 300 B GEN M3™ 300BLK RIFLE MAGAZINE FOR AR-15

PMAG® 30 AR 300 B GEN M3™ 300BLK RIFLE MAGAZINE FOR AR-15 Reviews & Ratings

The PMAG 30 AR 300 B GEN M3 is a purpose-designed magazine for rifles chambered in 300 Blackout® (300 BLK). Since its inception, 300 BLK shooters have had to use a magazine designed for another cartridge, limiting its ultimate performance and compatibility. One of the key features of 300 BLK is the compatibility with 5.56x45mm parts, but with the magazine, it is a compromise to do so. Due to the wide variety of projectile weights and profiles potentially decreasing overall reliability, a dedicated 300 BLK magazine was a logical step for the PMAG line.


In addition to the performance gained by a dedicated mag, the PMAG 30 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 30 AR 300 B’s distinct rib 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 Blackout performance, the PMAG 30 AR 300 B incorporates all of the GEN M3 features such as Magpul’s next-generation impact and crush resistant polymer, aggressive front and rear texture, an easily removable slim floor plate, and a paint pen dot matrix for marking and identification.


FEATURES
  • Purpose-built magazine only for 300 BLK
  • Dedicated magazine for rifles chambered in 300 BLK that supports the differing geometries found in that caliber. The result is a more reliable magazine
  • Designed with visual & tactile differences - Distinct rib design and smooth upper-half texture provide visual and tactile differentiation from other PMAGs to mitigate dangerous cross-loading issues
  • Incorporates the same features and performance of the Gen M3 line
  • Next-generation impact and crush-resistant polymer, aggressive front and rear texture, easily removable slim floor plate, and a paint pen dot matrix
  • Made in the USA.


SPECS
  • Caliber: .300 AAC Blackout
  • Platform: AR15, M4, M16
  • Capacity: 30 rounds
  • Weight: 5 oz.
  • Length, max: 7.5 in.
  • Compatibility: Wide compatibility with most 'STANAG 4179' platforms such as the AR15/M4, FN SCAR, IWI Tavor, and others



NOTE: DOES NOT INCLUDE DUST COVER.

See all of our AR15s and AR15 parts here.

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Reviews Summary
The PMAG 30 AR 300 B GEN M3 for 300BLK is widely praised for its reliability and performance, particularly with heavier rounds, addressing issues encountered with standard AR magazines. While most reviews highlight excellent feeding and the advantages of having a dedicated magazine, some users express concerns about rattling and perceived lower quality compared to earlier models. Overall, they are recommended for anyone using the 300 Blackout caliber.
What Reviewers Are Saying
Feeding Reliability
78%
Reviewers frequently note that the PMAG 300BLK magazines offer excellent feeding reliability, especially with heavier 300 Blackout rounds that standard magazines struggle with. Many users confirm that these magazines resolve feeding issues, making them a must-have for anyone using this specific caliber.
Product Quality
55%
While many customers are satisfied with the durability and fit of the magazines, there is a notable divide regarding perceived quality. Some users praise the construction compared to standard PMAGS, while others express dissatisfaction with the materials and feel of the Gen 3 models, highlighting issues such as rattling and less robust polymer.
Ease of Use
62%
Several reviewers appreciate the design that makes it clear these are dedicated 300BLK magazines. They find them easy to load and comfortable to handle, even noting improvements over traditional magazines, particularly in the context of mixed caliber use.
Availability and Pricing
48%
Reviewers mention availability issues and price fluctuations amid increasing demand for such magazines. Many express satisfaction with Brownells for having stock and fair pricing, even as comments regarding price gouging in the market are noted, suggesting a need for budget-conscious consumers to shop around.
Shipping Experience
50%
The shipping experience is generally praised, with multiple users noting fast delivery times from Brownells, enhancing their overall purchasing experience. Prompt shipping is seen as a significant advantage in their buying process, especially amid inventory scarcity.
5
The magazine that keeps on giving
These mags are top notch tough durable and long lasting will definitely be getting more
Would you recommend this? Yes, I would recommend to a friend
5
300 Blk-Out mags
Have not been able to use them yet, but I’m confident in the Magpul Brand ‘
Would you recommend this? Yes, I would recommend to a friend
5
300 blackout mags.
The ammo loads better in these mags, but haven’t test them yet. I’m hopeful they will work better than the regular 556 mags that I’ve been having trouble with.
Would you recommend this? Yes, I would recommend to a friend
5
Good for subs
I never intended to use 300 - specific mags but some of my sub loads don’t work well with the rib in a standard mag. This feeds a full mag of my Maker 190s just fine.
5
Mags
Solid product. Exactly the fit and finish I’d expect from Magpul.
5
Great Mags
They're made by Magpul what's not to like. They function great in all my ar's chambered in 300 block out
5
Feeds & Cycles As It Should
Although most 300 Blackout ammunition works well in a standard 5.56 PMAG, I was having issues with Hornaday's Subsonic 190 grain defensive ammunition. It would jam almost every time. With the 300 Blackout PMAGs that issue has been resolved.
5
These Blackout magazines are a good idea
I really like what Magpul did with these first off, they're easy to discern they're .300 Blackout and not 5.56, they're very comfortable to use just like the standard 5.56 Pmags. I definitely recommend them and I think they're a more reliable long term option than putting labeled rubber bands on your magazines. I chose to get mine from Brownell's because Brownell's usually has competitive pricing, and is a reliable and consistent standard in the gun community.
5
300blk magazine
What more can you say about Magplu Magazine s! I ran everything from 110gr to 205gr with out a problem! Just wished they had windows!
5
Perfect MAG for my SIG
These MAG's work flawlessly in my SIG MCX Virtus! Having a dedicated MAG for 300 BCK further enhances their usefulness so as to NOT get mixed with other calibers that could feed into the same mag well ; they are light weight but reliably sturdy!!