Mean Arms EndoMag: 9mm Conversion for 5.56/.223 PMAGs

Hrachya H
by Hrachya H
Mean Arms EndoMag 9mm Conversion for 5.56.223 PMAGs (1)

Mean Arms, the company known for making the AR-15/AR-10 magazine loaders, has introduced a new product called EndoMag. This is basically a 9mm conversion kit for 5.56/.223 Gen2 and Gen3 30 round Magpul PMAGs. The converted PMAGs will work with standard AR-15 lower receivers and Glock or Colt magazine compatible 9mm bolts.

Mean Arms EndoMag 9mm Conversion for 5.56.223 PMAGs (3)

The advantages of this product are that you can use an unmodified (no magazine well inserts or adapters) AR-15 lower receivers and turn your PMAGs into 9mm magazines. The disadvantage is that your 9mm magazine will have the dimensions of a 5.56 one. On the other hand, these magazines will fit in standard AR-15 magazine pouches and the magazine manipulations will feel the same as with standard AR-15 magazines.

Mean Arms EndoMag 9mm Conversion for 5.56.223 PMAGs (4)

Mean Arms EndoMag retains the last round hold open capability and also has a built-in ejector. According to the company, their magazine conversion works with 9x19mm ammunition loaded with all kinds of projectiles including hollow points. The EndoMag comes with a follower extension that limits the magazine capacity to 10 rounds to make it legal in the states with restrictive legislation. However, it can be easily modified to become a magazine of 15, 20 or 30 round capacity.

In order to convert the PMAGs into 9mm magazines, all you need is to disassemble the PMAG and replace the original magazine spring and follower with the Mean Arms EndoMag. This process doesn’t require a use of any specialized tools and doesn’t make any permanent modifications to your PMAGs – you can convert them back to 5.56/223 as easy as they were turned into 9mm mags. Below you can find a couple of videos demonstrating this product and the conversion process.

Right now the Mean Arms EndoMag is available for preorder at an MSRP of $24.99. The pack of three EndoMags will cost you $68.99.

I think folks at Mean Arms came up with a really great idea. If the quality and performance are as advertised, then I think this product will have a huge demand. What do you think about it? Let us know in the comments section.

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Hrachya H
Hrachya H

Managing Editor Being a lifelong firearms enthusiast, Hrachya always enjoys studying the history and design of guns and ammunition. Should you need to contact him, feel free to shoot him a message at

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