Magpul PMAG 20 AR/M4 GEN M3 5.56 NATO AR-15 Magazine - Black

Manufactured by Magpul Industries
Manufactured by Magpul Industries
171 Reviews

In Stock

Standard orders will ship out 1 business day if ordered by 3:30 pm CST, Monday-Friday. FFL orders will ship within 5 business days or less as long as we have the information for the transfer destination.

For individual Officer, First Responder, and Military pricing please make sure you are logged in. Click here for details

Magazines considered High Capacity are controlled by the ATF and/or local jurisdictions are not available for purchase/shipment in all areas.



The PMAG 20 GEN M3 is a 20-round 5.56 NATO polymer magazine for AR-15/M4 compatible weapons. This magazine features a long-life USGI-SPEC stainless steel spring, four-way anti-tilt follower and constant curve internal geometry for reliable feeding. A redesigned bolt catch notch in the rear of the magazine provides increased bolt catch clearance, while an over-travel stop on the spine helps ensure the magazine will not over-insert on compatible weapons.

Slim, for better compatibility with tight magazine pouches, this easy to disassemble magazine features a flared floorplate, low profile ribs, and aggressively textured front and rear surfaces for positive control. A paint pen dot matrix on the bottom panel of the body allows easy marking for identification.

  • Impact and crush resistant polymer construction
  • Constant curve internal geometry
  • Anti-tilt, self-lubricating follower
  • Long life USGI-SPEC stainless steel spring
  • Over-travel insertion stop
  • Ribbed gripping surface
  • Aggressive front and rear texture
  • Paint pen dot matrix panels
  • Flared floorplate
  • Pop-off impact/dust cover

NOTE: GEN M3 PMAGs may not be compatible with all billet lowers without slight modification of the magazine overtravel stop.

Magpul continues to grow and develop based on innovation, simplicity, and efficiency. At Magpul, mission driven requirements inform their product design, materials, and manufacturing, focusing on efficiency without sacrificing quality or performance.
See More


Caliber Gauge5.56 NATO
Magazine Capacity20
Manufacturer.Magpul Industries
PlatformAR-15 Magazines

WARNING: This Product can expose you to chemicals which is known to state of California to cause Cancer and Reproductive Harm. For more information, see

California Prop 65 warning

 WARNING: This product can expose you to chemicals, which are known to the State of California to cause Cancer and Reproductive Harm. For more information go to

Ratings & Reviews

171 reviews


Magpul mags 20 rnd


Have not had the chance to test these yet as my lower has not been released for ok by MD state. Have heard nothing but good about Magpul and look forward to positive results




My favorite mag


...bought this one as a gift for my neighbor. It's all good. :)

20 Round Magpul Gen M3 Magazine


20 Round mag will go good with my 300 BLK OUT due the cost of the AMMO !!

Great deal


20rd magazine was just what I was looking for. 30 mags are a little too big and some times get in the way. Magpul's mags are built to last and PA dose it rite.

Good Product


A newly found on-line outlet for all of my newly acquired AR 15 quality needs and upgrades.

First Order - No Problems!


After searching for weeks I finally found the Magpul Magazines I was looking for - in stock and at a great price. I placed the order online and in less than a week I had a box on my doorstep. My first stop for future purchases will be Primary Arms!

Great product _ great service


Always the best in products in rapid order!!

Good Mag


Another great Magpul Mag. Excellent, what else can you say???

High quality product and service!


As one would expect, these mags are great! Primary Arms is also great! They shipped out right away and took no time to get to my house. These PMags are high quality like all the others. I had issues with the M2 version not looking my bolt back and while I haven't put a ton of rounds through these they have locked back every time!