What if I told you a story where the US Army Enhanced Performance Magazines had 3 magazine related failures out of 6000 rounds, and the PMAG had 2 magazine related failures out of 6000 rounds. Would you assume that the EPM was 50% worse than the PMAG Gen3? Or would you do the math to show that the EPM was 99.95% reliable and the PMAG Gen3 was 99.97% reliable?
If you start pulling the non-magazine related malfunctions from the EPM from the data provided here for the M16A4 those reliability numbers are actually pulled from one of the tests: http://www.thefirearmblog.com/blog/2017/07/21/us-armys-new-magazine-failure-usmc-test-enhanced-performance-magazine-shows-performed-worse-predecessor-pmag/ Odds are you are familiar enough with statistics to figure out that anything above 98.5% reliability is very good, as you are talking single digit differences.
Of course if you actually do that level of analysis, you’ll come up with all sorts of questions about why the USMC chose to explain SOME failures, but not others. Of course none of this has stopped Congress or pundits from outright demanding that the US Army follow suit of the USMC and purchase PMags. http://www.nationalreview.com/article/449569/army-ammunition-magazine-substandard-must-go
Heck, lets look at the worst case where the USMC found 24 stoppages (17 of which were “light strikes” which isn’t magazine related) using the USN/USMC only Mk318 load is still 5,976 out of 6000 rounds for 99.6% reliable.
Honestly it doesn’t really matter whether you equip the Army with PMag Gen3s or not, the difference in reliability between that an the standard USGI magazine isn’t what wins wars. Congress has also decided that rifle magazines are an “ability-one” purchase item, so unless Magpul can become a disabled owned and operated business, is not likely to become the official provider for M4A1 magazines for the US Army any time soon (and PMags already have an NSN for units to purchase through the supply system although they are not standard issue). Any elected officials who hold hearings about magazine reliability and demand answers as to why the Army doesn’t just buy PMags really needs to shut up before someone points out that it is a Congressional mandate that makes weapon magazines an “ability-one” item which is why “Center Industries” of Wichita, Kansas has continually provided the US Army with magazines, despite having no commercial magazine sales to the public…
A more plausible reason the USMC wants Gen3 PMags is that the M27 automatic rifle didn’t work well with the Gen2 PMags. The Gen2 PMags have served just fine in M4 and M16s for years, but for some reason they didn’t work so well with the H&K system.
The Army testing for the EPM with M855A1 and M4A1 indicated a 300% increase in reliability as measured in mean time between stoppages, and were fielded to 2/75 Rangers first before any other Army unit which is a pretty good indication of confidence. 300% from http://www.dtic.mil/ndia/2014/armaments/WedLucas.pdf and “98.32% Probability of completing a 209 round mission without failure (Reliability – 13,973 MRBS as a system)” from http://www.dtic.mil/ndia/2015/smallarms/Russell.pdf
So, what does this mean for you? Probably nothing. If you are a private citizen you can run your gun how you want, and you are probably not firing a lot of M855A1 where either a PMag Gen3 or EPM would be necessary to avoid early wear. In your case, you just want reliable magazines.
In terms of reliable magazines, if you’ve got tan follower magazines, or have upgraded green or black follower USGI magazines with a Magpul anti-tilt follower (and might as well add new springs, they are cheap). If you’ve got PMags, by all means stick with them until you wear them out, they are good mags. But if you don’t have PMags, no need to go out and spend a lot of money getting all new PMags unless you want to.
For those who have a lot of old black or green follower mags, I really do recommend the Magpul upgrades, as there really is nothing more frustrating than having all the ammo in your mag fall to the dirt because the follower bound up in the body (which happened to me a number of times with the old black and green follower mags). Link for spring and follower kit: http://www.brownells.com/magazines/rifle-magazines/magazine-parts/magazine-followers/ar-15-m16-usgi-magpul-follower-ss-spring-kits-prod80186.aspx or if you just need the followers: https://www.midwayusa.com/product/2319633504/magpul-enhanced-self-leveling-magazine-follower-ar-15-polymer-package-of-3