PMag (and others) life cycle

[Elwin]

What's your rationale for doing it with pistol mags? Perhaps it's a naive viewpoint on my part, but outside of scenarios involving non-sealed ammo in humid climates, if the ammo doesn't go bad sitting in an ammo box, why would it go bad sitting in a mag?

Pistol mags and the bullets in them, in my view, are subject to a lot of abuse, though I should clarify that I’m mainly talking about mags in carry guns or that are carried as spares. Those ride around pressed against my body all day and move around with me, which also means going through all the climate and humidity changes I do.

I agree that with a mag that sits and does nothing, the ammo isn’t suffering any more abuse than boxed ammo, so I guess my question RE changing out rifle bullets is only relevant if it’s due to handling the ammo if and when you rotate out the mags.

[olstyn]

I agree that with a mag that sits and does nothing, the ammo isn’t suffering any more abuse than boxed ammo, so I guess my question RE changing out rifle bullets is only relevant if it’s due to handling the ammo if and when you rotate out the mags.

I would personally be unlikely to bother with changing out the mags or the ammo in that scenario, as I have a hard time believing either would see any significant stress in a temperature controlled indoor environment.

[HCM]

Also no answers but I have a related question or variation on the same question I was thinking of starting a thread for; do people tend to change out loaded Pmags, and their ammo, and if so how often?

I have Pmags dedicated to defensive use that don’t get used at the range aside from initial testing. I’m also not chambering the rounds. Should they be on a once yearly schedule of fire all the ammo and replace with a whole second set, like I already do with pistol mags? That’s doable but if it’s not necessary I’d skip it, given the price of that many rounds of Federal Fusion MSR.

Once again, it depends.

These mags are sitting loaded on your climate controlled house ? They will outlast you.

Sitting in a vehicle lock box exposed to extreme heat, cold, and condensation ? Carried every day, exposed to dirt, crud, weather and in the case of Pmags UV light? different story.

The main issue with chambering / rechambering rounds (other than bullet setback) is impacts on the primer can dislodge the anvil inside the primer cup resulting in a dead primer. With handgun rounds you can usually chamber 3 or 4 times without issue. With rifles such as ARs one and done is the best policy due to the more concentrated impact of the firing pin.

[Clusterfrack]

Out of maybe 20 PMags I have in use, one FDE mag cracked a feedlip. I’ve kept some loaded for over 5 years with no covers, and they work fine. Two were run over by a truck, and another by an ATV. They still work.

But I still prefer Lancer AWMs because they seat easier and seem to be more resistant to suppressor crud.

[Willard]

I keep majority of my ammo stored in magazines for obvious reasons. I've kept first gen MagPul released to market fully loaded with the covers for years with no indication of problems whatsoever.

[Tensaw]

I've have hear about, but not actually seen, cracking of the feed lips due to the pressure of the top round n a loaded mag constantly pressing against the feed lips. As a result I keep two mags immediately ready for use, but the rest of my loaded mags are kept with the "dust cover" in place, as that presses down on the top round relieves the pressure on the feed lips. Every few months I rotate which of my mags are the ones kept "ready," without the "dust cover" on.

After eight years with 2 dozen fully loaded PMags I haven't had any signs of cracking.

The (slightly down-loaded) mag inserted locked kept locked into the mag well of an AR gets the same benefit as the dust covered ones, yes? In that the top round is somewhat compressed into the mag body by the underside of the bolt carrier thus taking pressure off the feed lips? Am I correct about this?

[DMF13]

The (slightly down-loaded) mag inserted locked kept locked into the mag well of an AR gets the same benefit as the dust covered ones, yes? In that the top round is somewhat compressed into the mag body by the underside of the bolt carrier thus taking pressure off the feed lips? Am I correct about this?

I suppose that would be correct, but haven't thought about it much. I just keep 30 rounds in all of them, and rotate which ones are the two that don't have the "dust covers," and the other that do.

[Nephrology]

Duane Liptak from Magpul posted this on M4Carbine a while ago re: dust covers:

No need for dust covers. They help keep junk out and protect against significant falls, like speedball deliveries, but no need at all for feed lip concerns, even heat cycling. We spend a lot of time testing for that, and have multiple generations of magazines stored loaded in heat cycling conditions for continuous verification.

[UNM1136]

I have had 2 PMAGs crack at the spine. The most recent PMAG failure I had was a chip out of the mag catch recess that caused intermittent falls from the magwell under recoil. Despite the RMs screams to push/pull, it was equipment caused, so no Moose Cock...

In the same amount of time I have gotten rid of almost half a dozen USGI Al mags for various reasons.

pat

[WobblyPossum]

I’ve had one Gen2 Pmag crack at the spine. As far as I remember it still feeds live rounds but I’ve relegated it to being a dry fire magazine for practicing reloads. Haven’t had any issues with a Gen3 Pmag yet.