Lancer L5 Advanced Warfighter 20 Round .300 BLK AR-15 Magazine

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Dead Air Armament Keymount Flash Hider - .308 Win/7.62mm – 5/8×24

Dead Air Armament Keymount Flash Hider - .308 Win/7.62mm – 5/8×24


20 Round .300 Blackout Magazine for Subsonic Rounds

This 20 round .300 Blackout specific magazine alleviates issues with stacking and feeding of 200+ grain subsonic rounds. The enlarged body allows each cartridge to stack without tipping, and the hardened steel feed lips ensure round retention before moving into battery. The shortened length for this magazine is also better for shooting prone or with a bipod, perfect for hunting applications.

This magazine is made for the AR-15/M4/M16 family, for rifles chambered in .300 Blackout. But any rifle that is chambered for .300 that takes AR magazines will likely work better than stock AR-15 mags for 5.56.

Designed, tooled, manufactured and assembled in the USA.

Weight 4.4oz


  • Specifically made to feed .300 BLK
  • Hardened steel feed lips
  • Impact resistant polymer body
  • Easily visible round count markers in translucent version
  • Top of magazine catch is steel
  • Non-tilt follower
  • Constant curve internal geometry
  • Stainless steel spring
  • Aggressive texturing on body for positive grip
  • Slim body design
  • Slide on bottom, easy to disassemble

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Have Questions About this Product?

The AT3 Tactical store has a 90 day no-hassle return policy for products in good condition. You can view the full details of our return policy here.

If you encounter an issue or defect with a product after 90 days of your purchase, you can refer to the manufacturer for a warranty claim. Their policies are below.

Lancer Firearms Returns for Warranty Work

It is legal for you to ship your firearm to us for warranty work and for us to return it directly to you without going through a dealer unless Lancer Systems, LP learns that the ship-from address is a location where firearms are prohibited. You must provide us with a street address for the return UPS shipment and you must be the signer when UPS returns the firearm.

We are required by BATF to have the firearm owner’s signature by UPS for legal return. If the shipped from the address is a prohibited location, the repaired firearm will not be shipped until an FFL is nominated to receive the repaired firearm for the owner.

Do not attempt to use the postal service to ship a firearm. Use UPS service only as they are the only services with access to our secured shipping area. We are not responsible for incoming shipping damage and will contact you if we have determined that your shipment has been damaged in transit to us.

Requirements for shipping your firearm to us:

Prior to shipping, remove all stocks, scopes, mounts, and accessories from your firearm unless they are necessary for the work to be done. This will further reduce your risk and save you additional labor charges.
If you use original factory boxes or after-market cases, we recommend inserting them into another plain box so as not to have any indication that a firearm is enclosed.

Make sure that the firearm is well packed to prevent movement and damage in shipment. There should be a buffer of at least one inch of packing material between your firearm and the wall of the box.
If you do not have shipping boxes and/or packing materials to ship us your firearm, supplies are readily available at shipping outlets like the UPS Store or from office supply outlets like Staples.

Address: 2800 Milford Square Pike, Quakertown, PA 18951 United States

Return Policy

You may return most new, unopened items within 30 days of delivery for a full refund. We’ll also pay the return shipping costs if the return is a result of our error (you received an incorrect or defective item, etc.).

You should expect to receive your refund within four weeks of giving your package to the return shipper, however, in many cases, you will receive a refund more quickly. This time period includes the transit time for us to receive your return from the shipper (5 to 10 business days), the time it takes us to process your return once we receive it (3 to 5 business days), and the time it takes your bank to process our refund request (5 to 10 business days).

Disclaimer: Manufacturer’s warranty is subject to change without prior notice.

Customer Reviews

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