The Magpul-designed PMAG is very popular among Joes and Grunts in the Box. With its high-impact resistant plastic construction, textured grip and MagLevel window for round count verification, the PMAG is a versatile alternative to the standard-issue mag -- which as you all know had some troubles before the Army's redesign.
But PEO's Col. Doug Tamilio warns that after-market mags made from polymers may not hold up to the rigors of Soldier operations, so that's why the service stuck with aluminum for its improved mag.
Through testing, we know that the aluminum magazine is the most durable magazine there is for its weight. We also know that certain plastics do not work in all operational environments. In extreme cold, they can crack. When you expose them to different types of lubricants and things, they can corrode.
Soldier say the new Improved Magazine resolved the follower issue and spring wear which caused jams in previous versions. But the Soldier who asked about the PMAG noted that aluminum is actually less durable than the plastic PMAG and, interestingly, the Army magazine can give away your position during night ops if it clanks against something. The PMAG is a lot quieter, the Soldier said.
Now Tamilio also said for units who have some petty cash to spend before deployment for some unit gear, PEO is going to release shortly a list of approved products Joes can buy off the books -- and we presume the list will include PMAGs.