View Full Version : PMAGs- Tested Past Destruction....

24 February 2008, 15:26
By this point, everyone has seen video of PMAGs getting run over by cars, trucks, HUMVEES, 5 ton military vehicles, and just about every other vehicle in commercial or military use. The point has been made that PMAGs will take abuse that will kill standard USGI aluminum magazines, and even the substantially more expensive steel HK magazines.

However, there comes a time where Murphys law steps in, and equipment is damaged. The idea behind this round of testing was to start out with a known good weapon and magazine, and then damage the magazine to find its failure point.

Below is the host weapon that we ran for this block.

Components are as follows:
M4 cut upper receiver
MIL prototype DD A2 RIS rail
Prototype Melonite/ Tennifer (proprietary but similar treatment) barrel
MI Folding front and rear BUIS
Eotech 552
AAC SCAR Light Suppressor
Bobro VFG

Verification firing before actual testing was conducted with several Magpul PMAGs, as well standard USGI magazines to ensure there were no existing problems.


24 February 2008, 15:27
From my work in the military, police work, and as an instructor, I've observed the usual failures of M16/AR15 magazines come from damaged feedlips, and weak springs.

This can occur from long term storage of loaded magazines, but more typically, its from accidents and neglect when we look at the feed lips. Loaded, partially loaded, and even empty magazines are often dropped or stripped from the magwell only to find themselves landing feedlips down onto concrete, rocks, or other hard surfaces. This type of damage is accidental, and par for the course. The last thing we would expect of anyone is to train differently than they fight, and I understand that there are plenty of people who will never use a dump pouch for recovery of magazines. The vast amount of LE training that I've ever been involved with neglects a dump pouch as its simply not something that an officer is going to carry with them. In the LE scope of operations, magazines are a expendable item and resupply is as far as as your next shift, HQ, or the trunk of your cruiser, . I'm not talking about refusing to conduct tactical loads when I say this, however I don't want to stray offtopic into a tactics discussion.

Secondly we have neglect, and by that I mean people dropping their magazines while being issued, cleaning them, storing them, or any other number of ways that people drop loaded and empty magazines without being in a firing relay. Crushed magazines from being stepped on probably runs a close second, and the feedlips are an obvious week spot.

Whether from being dropped, stepped on, or crushed by equipment, the feedlips are an inherent weak spot in the design of any magazine.

Magazine springs have come a long way over the years, and while rotation of mag springs is certainly something worth considering, it is something that I think is often blown out of proportion. The green, but especially older black military followers were notorious for inducing feed problems with anything but full strength springs. Replacement of those followers with the smoother feeding newest generation of anti-tilt followers has shown to eliminate many of those problems. Magpul, CMMG, and a few others make improved followers. I've had personal good luck with the Magpul enhanced followers, but heard good things about the CMMG as well (I've not tried them myself).

Shown below are the feedlips of the Magpul PMAGs with some T&E ammo. This is not the ammunition used in this block of testing, as its design is obviously more conducive to feed problems.



24 February 2008, 15:27
For the purposes of this testing, the feedlips of the FDE Windowed PMAG were smashed intentionally (through throwing and hammering it into a rock), and repeatedly until the spine displayed a estimated 2" crack, and one of the feedlips had a crack which ran almost its full length. Throughout all of the abuse, the windowed section never came loose or showed any signs of fatigue.

After running three mags through the now fractured PMAG, it continued to feed and function without any problem, so we decided to cause more damage, and find its failure point.



24 February 2008, 15:28
After the above having no problems, we decided that the crack down the spine, while impressive in looks, had no real bearing that we could determine when it was locked into place in the magazine well. Its possible that the magazine simply goes back into its molded position when compressed, but thats just a guess.

The object of the testing was to determine at what point the PMAG would fail, and so far, we hadn't reach it. While it was obviously not in the condition you would want to carry it in for duty use, it doesn't change that it still continued to load and fire over and over.

To increase its failure possibility, we decided to rip off the section of feedlip that had cracked. With the section removed, I felt pretty certain that we would be ending the test, however, I was both surprised, and incorrect in my estimation of what the PMAG could take in terms of damage, and still remain functional. Another three magazines were fired, and there were no problems with ammunition feeding, firing, or with spent casings get caught up.

In the below pictures, you can see the portion of feedlip that was ripped off the PMAG.



24 February 2008, 15:29
Taking a quick break from the PMAG testing, I placed the weapon down, and the suppressor made contact with some wood that was soft and pulpy. The result was a can that had wooden pulp seared to it. Thankfully, after we let it cool down, we fired it enough that it reheated and burned/ cooked off the material off the surface of the suppressor.

Whatever AAC is using for a finish on this can is impressive to say the least.


24 February 2008, 15:29
The next step in moving towards failure was putting a round through the magazine. While not something that I would consider a realistic part of magazine testing, it is something that has happened in combat. If nothing else, it would be another step towards the eventual demise of the magazine.

We fired a single round through a partially loaded PMAG, and the results are pretty clear in the below pictures. As expected, while a Magpul has done a nice job of creating a functional polymer magazine, it certainly isn't bullet resistant. What wasn't expected was that the remainder of the magazine would seat, and fire without any trouble. The magazine was reloaded two more times (full 30 round load). It loaded without any problems, inserted into the magazine well without trouble, and fed and fired all rounds with only one round failing to feed. This I attribute to using a new dry lube for the test, and the weapon had been running VERY scratchy and it felt horrible when working the charging handle. While I feel that it was not a magazine related issue, it still occurred, so its worth mentioning.




24 February 2008, 15:30
After firing one round through the body of the magazine, and finding it still functional, the next step was pretty obvious. This time we fired a second round through the body of the PMAG. After picking the magazine up, it was clear that this second shot had done more damage as it had cut the magazine spring. Again we loaded the magazine, and this time we found that it would not load to full its previous 30 round capacity. It was now a 16 round magazine, but we loaded it and fired through its reduced capacity another three times without any trouble.

Below you can see the end result of our "PMAG Tested Past Destruction", though perhaps the title is a little misleading. While there is no question that we damaged the magazine, the idea of destruction implies that an item has been rendered ineffective or useless, and that is clearly not the case.





24 February 2008, 19:19
A full overview of the Magpul PMAG, including a little of its history can be found at the following thread.

Magpul PMAG General Review Link (http://www.weaponevolution.com/forum/showthread.php?p=2109#post2109)