People have been wanting the Magpul Pmag 40 rounder out for sell ever since seeing the teaser prototypes. The recent foolish attempts by those who think they are our rulers, also exacerbated the desire to get the 40 rounders out. Finally the Pmag is now out in a 40 round capacity in the new 3rd generation of Pmags.
As a way to compare directly, above is a AWM Lancer, the 40 round Pmag and a Surefire 60 round magazine. As far as length goes, if I was looking at it solely from that point of view. I would certainly take the 60 over the 40 being its more ammo and the length is so close as to not matter. In fact, the Surefire is a bit shorter though it is wider.
While I see the 60 round SF as the kind of mag you keep in the gun for breaking an ambush, or full auto fire like the IAR or a game mag, the Pmag is closer to being something I could see being more of a standard carry item.
The 40 round mag does stick up out of pouches more of course, but its not a absurd amount. I would limit its use for game use at this point though, until purpose made pouches come out. You can see that they are workable though.
This is two 40s crammed into my ten speed pouches on my plate carrier. Not great, but you can do it. When used on a belt for game use, the amount they stick up is nothing I can see worrying about.
I want to mention that while they seem to be weighing down my belt and want to break the FastMags away, the problem is I actually put the belt on over top another belt with a double pistol mag pouch resting under the belt with the Pmags. When the belt is worn properly, everything is nice and snug. It is only 10 more rounds after all.
As a last side by side, here is a 40 rounder in a “krinkov.” The AK mag is 45 rounds, but the 40 round Pmag makes the MK18 a much better choice in every way to the PDW/subcarbine role the krink is excellent at being.
Now, as far as reliability goes, its a Pmag. I can go on and on with pointless filler blather about it, but most know how well a Pmag works. If you have a Pmag those does not work, its your gun, not the Pmag 999 times out of 1000. Sorry if that cause anal discomfort but its the truth. As an aside I think the Lancer AWM is like a perfect Pmag but that is off topic. I do feel strongly enough about the quality of the Lancer AWM that I try to spread the word often.
I purchased 3 of the new forty rounds Pmags and set to abusing them over the weekend. The first testing was done with the help of my friend where we did testing in a few guns to make sure the bolt locks open and the mag drops free. I went on to do my usual testing of resting the gun on the mag as a mono-pod, putting pressure on it front back and side to side etc, to get it to fail. No problems. I and my friend fired mag dump after mag dump as fast as we could work the trigger with no problem
While the lower on the MK18 got so hot that I could not touch it with the bare hands, th emag worked fine. The reason for using the SBR is the common myths of the SBRs not being reliable, so I figured if it would have a problem, the SBR might cause it. OF course the Colt MK18 worked as I fully expected and so did that magazine.
The carbine often got so hot that we had to be careful handling it since we forgot to wear gloves. This resulted in the gun smoking after each mag dump.
The mags all worked in the usual magpul way. Loading the mags are not hard either. I thought the spring would get pretty stiff by the last few rounds, but its not bad at all. I also could not discern any extra effort needed to insert a full mag on a closed bolt. That was a nice surprise for me since I did not expect it, and the follower is nice and smooth.
The mags come with the standard dust cover and have the new floor plate that will not take the older generation adapter sadly. As far as I know, the new mags are in black only.
I am still pleased with the Surefire 60 rounds mags since i have not had a problem with mine nor has any other Looserounds staff had a problem, but I like the idea of the 40s. Its a little more but more compact. It will take a few months before I really trust them for a fight like I do the 30 round Pmag, but I can see no real reason to worry. I just like to let something become proven over time, Magpul is certainly capable of making fine magazine, so I take that into account, but it is a new mag with a new shape so I will wait and make sure. As for now, after a year I tentatively trust the surefire 60s, and after another year , I will feel comfortable with them in use other then training or match use. The 40 round Pmag, not being as drastic is almost surely completely worry free, but I would advise doing thorough testing anyway.