AR PMags left fully loaded. Bad idea?

Pond, James Pond · March 14, 2015, 02:30 PM

I'm planning on buying perhaps another 4 mags for the AR.

I like PMags, but the guy I'd buy them from said that they are not as good as metal mags because the tabs at the top of the mag that you feed rounds between when loading tend to get fatigued if left loaded for a long time, to the point of flexing out and either meaning there are feed issues or problems getting the mag into the well.

He said he'd seen it happen a number times in his capacity as R.O., R.M. and club manager.
Also unloading mags every time would be a pain for me.

Have you had this problem?

psalm7 · March 14, 2015, 03:16 PM

I know someone that has a duffle bag full of GI Surplus mags loaded with green tips . He has had these stored for near 25 years and swears they will be just fine .
I keep my firearms with a loaded mag in them and some may sit a year or so befor they are shot and they always work as they should .
That includes a Ruger Mini 14 with PMags .

Mention of Pmags on last sentence .

Pond, James Pond · March 14, 2015, 03:24 PM

This was specifically about Pmags. Gen 2 in my case.

Do polymer PMags suffer from excessively flexing flanges if left loaded?

Nodak1858 · March 14, 2015, 03:55 PM

I have a bag of loaded Pmags I keep in my range bag. When I shoot I run through them and then when I get home I load them back up to 30 rounds. I have done this for three years. I have had no issues with any of the Pmags or any of my other mags for that matter. I would have no hesitation to keep doing this indefinitely.

Nodak1858 · March 14, 2015, 03:56 PM

Sorry forgot to add, all my Pmags are gen 2.

skizzums · March 14, 2015, 04:54 PM

your gun shop guy must know something that the 20 million of us over here don't. I haven't ever seen a worn out PMag, I have many, I also like CAA. but who knows, I wasn't thinking 50 years ahead when I bought them. I would honestly think that the scenario he is speaking of, if actually occurring, would happen with metal more than polymer

polymer usually turns brittle over extended periods of time, since it essentially never stops curing, so I think "flex" wouldn't be the long-term issue to worry about, the opposite in fact

Jo6pak · March 15, 2015, 05:31 PM

Load them and snap the little cover in place.
The cover is designed to take the pressure off the feed lips. I store 3 loaded all the time, never had an issue in the years I have used them.

You'll be good to go.

Mosin-Marauder · March 15, 2015, 08:59 PM

An unloaded magazine is as useful as a car without gas.

Pond, James Pond · March 16, 2015, 01:45 AM

Quote:

An unloaded magazine is as useful as a car without gas.

You can sleep in a car!

Quote:

Load them and snap the little cover in place.

Plastic cover? What plastic cover?

I have no plastic covers....

hso · March 16, 2015, 09:58 AM

I can understand your concern about the feed lips deforming enough to affect function, but I have used older Pmags that sat for over a year loaded without any apparent degrade in function. You may find otherwise.

scsov509 · March 17, 2015, 02:13 PM

Quote:

That includes a Ruger Mini 14 with PMags.

How are you able to use a PMag in a Mini-14 when the magazine design between the AR and Mini are totally different from one another?

OP, I'm another guy who keeps a pretty large quantity of PMAGs loaded up that I empty through the year, and I've never had any issues with feed lips. That is reportedly why Magpul originally included the dust cover, but I rarely use mine anymore and still haven't had any problems.

Dragline45 · March 17, 2015, 02:55 PM

Quote:

your gun shop guy must know something that the 20 million of us over here don't. I

It's pretty well known by now that leaving Pmags loaded to full capacity can cause then to crack at the feed lips and spine, no different than aluminum USGI feed lips bending from being left loaded to full capacity. 9 times out of 10 it won't be an issue, but it has and can happen. The least likely to give you problems at the feed lips are stainless steel mags.

Ridge_Runner_5 · March 17, 2015, 03:25 PM

Quote:

Plastic cover? What plastic cover?

I have no plastic covers....

They stopped including them with M2 MOE magazines.

https://www.magpul.com/products/pmag...%C2%AE--3-pack

scsov509 · March 17, 2015, 05:15 PM

Quote:

It's pretty well known by now that leaving Pmags loaded to full capacity can cause then to crack at the feed lips and spine, no different than aluminum USGI feed lips bending from being left loaded to full capacity. 9 times out of 10 it won't be an issue, but it has and can happen. The least likely to give you problems at the feed lips are stainless steel mags.

Well known because it's written about on the internet and widely experienced are two different things, and this "problem" as far as I can tell is widely written about online but strangely never actually experienced by me or anyone I know. I watch PMAGs get left loaded and shot every six months at in-service training, some times every other in-service for that matter, and none of them ever fail. I have 30-35 PMAGs personally that are basically loaded all the time, they get emptied on the range periodically and then get loaded right back up and stored again, but I've never had any feed lips fail. I've had springs give up on me, had magazine bodies break when they've been dropped loaded on a concrete floor, even had followers seize up because they're all kinds of gunked up from excessive shooting and no cleaning - but I've never had feed lips give out because they've been stored loaded too long.

So I think you're right when you say 9 out of 10 times it won't be an issue - probably 99 out of a 100 times or 999 out of 1000 times it won't be an issue. IMO this is one of those problems created by guys who spend a lot more time behind the keyboard than behind the gun, because from what I actually see - and I shoot an awful lot these days - it's a "problem" written about a lot more than actually experienced.

Dragline45 · March 17, 2015, 08:00 PM

Quote:

Well known because it's written about on the internet and widely experienced are two different things, and this "problem" as far as I can tell is widely written about online but strangely never actually experienced by me or anyone I know.

While I cant have Pmags in MA because they are not pre-ban, my buddy who is an LEO has dozens of them and had 2 split at the spine from being left loaded. These mags didn't see heavy use either, they mostly just sat in the safe loaded. With that said both of them still functioned after cracking, but that experience made him buy a bunch of USGI's to have laying around as well. Like I said the majority of Pmags will never experience cracked spines or feed lips from being left loaded, but it can and has happened.

psalm7 · March 17, 2015, 11:19 PM

Pmags / Poly mags . Poly mags made for lots of firearms .

Theohazard · March 18, 2015, 01:20 AM

Quote:

Originally Posted by psalm7

That includes a Ruger Mini 14 with PMags .

Quote:

Originally Posted by psalm7

Pmags / Poly mags . Poly mags made for lots of firearms .

No, PMags are a type of magazine made by Magpul, and that's what this thread is about. There are no PMags made for the Mini 14.

scsov509 · March 18, 2015, 03:52 AM

Quote:

While I cant have Pmags in MA because they are not pre-ban, my buddy who is an LEO has dozens of them and had 2 split at the spine from being left loaded. These mags didn't see heavy use either, they mostly just sat in the safe loaded. With that said both of them still functioned after cracking, but that experience made him buy a bunch of USGI's to have laying around as well. Like I said the majority of Pmags will never experience cracked spines or feed lips from being left loaded, but it can and has happened.

Quote:

I like PMags, but the guy I'd buy them from said that they are not as good as metal mags because the tabs at the top of the mag that you feed rounds between when loading tend to get fatigued if left loaded for a long time, to the point of flexing out and either meaning there are feed issues or problems getting the mag into the well.

He said he'd seen it happen a number times in his capacity as R.O., R.M. and club manager.

If there's really a widespread issue with PMAGs then I'm hoping at some point we're going to hear something more than "Well I know this guy..." or "I was told at the local gun store." If it's really a "widely known" problem then I'm certain we're going to start seeing all those first hand accounts and lots of pictures come along at any time now, right?

Dragline45 · March 18, 2015, 06:12 PM

Quote:

Originally Posted by scsov509

If there's really a widespread issue with PMAGs then I'm hoping at some point we're going to hear something more than "Well I know this guy..." or "I was told at the local gun store." If it's really a "widely known" problem then I'm certain we're going to start seeing all those first hand accounts and lots of pictures come along at any time now, right?

By the way that guy I mentioned is one of my shooting buddies and I saw them first hand. Not sure if he still has them but I'll see if he can send me a few photos if he does. But since you asked, here are a few pics of Pmags cracking along the spine.

silverstang23 · March 18, 2015, 06:31 PM

I don't think you can do anything wrong with a Pmag, including run it over with a car. What good is an empty magazine going to do you?

March 14, 2015, 02:30 PM	#1
Pond, James Pond Senior Member Join Date: July 12, 2011 Location: Top of the Baltic stack Posts: 6,079	AR PMags left fully loaded. Bad idea? I'm planning on buying perhaps another 4 mags for the AR. I like PMags, but the guy I'd buy them from said that they are not as good as metal mags because the tabs at the top of the mag that you feed rounds between when loading tend to get fatigued if left loaded for a long time, to the point of flexing out and either meaning there are feed issues or problems getting the mag into the well. He said he'd seen it happen a number times in his capacity as R.O., R.M. and club manager. Also unloading mags every time would be a pain for me. Have you had this problem? __________________ When the right to effective self-defence is denied, that right to self-defence which remains is essentially symbolic. Freedom: Please enjoy responsibly.

March 14, 2015, 03:16 PM	#2
psalm7 Senior Member Join Date: March 7, 2014 Location: Middle TN Posts: 543	I know someone that has a duffle bag full of GI Surplus mags loaded with green tips . He has had these stored for near 25 years and swears they will be just fine . I keep my firearms with a loaded mag in them and some may sit a year or so befor they are shot and they always work as they should . That includes a Ruger Mini 14 with PMags . Mention of Pmags on last sentence . Last edited by psalm7; March 14, 2015 at 04:51 PM.

March 14, 2015, 03:24 PM	#3
Pond, James Pond Senior Member Join Date: July 12, 2011 Location: Top of the Baltic stack Posts: 6,079	This was specifically about Pmags. Gen 2 in my case. Do polymer PMags suffer from excessively flexing flanges if left loaded? __________________ When the right to effective self-defence is denied, that right to self-defence which remains is essentially symbolic. Freedom: Please enjoy responsibly.

March 14, 2015, 03:55 PM	#4
Nodak1858 Senior Member Join Date: September 7, 2009 Location: N. Dakota Posts: 435	I have a bag of loaded Pmags I keep in my range bag. When I shoot I run through them and then when I get home I load them back up to 30 rounds. I have done this for three years. I have had no issues with any of the Pmags or any of my other mags for that matter. I would have no hesitation to keep doing this indefinitely. __________________ We've all heard that a million monkeys banging on a million typewriters will eventually reproduce the entire works of Shakespeare. Now, thanks to the Internet, we know this is not true.

March 14, 2015, 03:56 PM	#5
Nodak1858 Senior Member Join Date: September 7, 2009 Location: N. Dakota Posts: 435	Sorry forgot to add, all my Pmags are gen 2. __________________ We've all heard that a million monkeys banging on a million typewriters will eventually reproduce the entire works of Shakespeare. Now, thanks to the Internet, we know this is not true.

March 14, 2015, 04:54 PM	#6
skizzums Senior Member Join Date: July 1, 2013 Location: Douglasville, Ga Posts: 4,615	your gun shop guy must know something that the 20 million of us over here don't. I haven't ever seen a worn out PMag, I have many, I also like CAA. but who knows, I wasn't thinking 50 years ahead when I bought them. I would honestly think that the scenario he is speaking of, if actually occurring, would happen with metal more than polymer polymer usually turns brittle over extended periods of time, since it essentially never stops curing, so I think "flex" wouldn't be the long-term issue to worry about, the opposite in fact __________________ My head is bloody, but unbowed

March 15, 2015, 05:31 PM	#7
Jo6pak Senior Member Join Date: August 5, 2010 Location: West Coast...of WI Posts: 1,663	Load them and snap the little cover in place. The cover is designed to take the pressure off the feed lips. I store 3 loaded all the time, never had an issue in the years I have used them. You'll be good to go. __________________ NRA Life Member, SAF contributor.

March 15, 2015, 08:59 PM	#8
Mosin-Marauder Senior Member Join Date: April 18, 2014 Location: North Carolina Posts: 2,320	An unloaded magazine is as useful as a car without gas. __________________ Proud owner of three (four-ish) pieces of history! K-31, Mosin-Nagant M91/30, M24/47 Mauser, Norinco SKS. "You might as well appeal against a thunderstorm..." William Tecumseh Sherman

March 16, 2015, 09:58 AM	#10
hso Senior Member Join Date: May 10, 2002 Location: Appalachia Posts: 170	I can understand your concern about the feed lips deforming enough to affect function, but I have used older Pmags that sat for over a year loaded without any apparent degrade in function. You may find otherwise. __________________ TANSTAAFL

March 17, 2015, 11:19 PM	#16
psalm7 Senior Member Join Date: March 7, 2014 Location: Middle TN Posts: 543	Pmags / Poly mags . Poly mags made for lots of firearms .

March 18, 2015, 06:31 PM	#20
silverstang23 Senior Member Join Date: May 27, 2013 Posts: 180	I don't think you can do anything wrong with a Pmag, including run it over with a car. What good is an empty magazine going to do you?