Magazine question.

[Opie610]

Can anyone tell me if it is alright to keep the magazines loaded for my M&P's? Just wondering if it will weaken the spring over time or not.

Thanks in advance for your input.

[KINGOWOOD]

Load em up, won't hurt the springs. Personally I load em 1 short of maximum cap. Mags from Vietnam are still going today.

[bac0nfat]

They will be fine. They wear out from thousands of cycles, not constant pressure.

MODS please make a sticky thread about mag springs!

[rwb1500]

They will be fine. They wear out from thousands of cycles, not constant pressure.

MODS please make a sticky thread about mag springs!

Word. Load 'em up.

I heard a story once about a widow of a Gunnery Sgt who served in WWII. The widow brought a 1911 and some loaded mags to a gunshop to sell it 20 years after the gunny had died. The mags still worked fine.

[39flathead]

Coil over strut springs on a 2000lb car are semi-compressed all the time, it's the constant "unloading & over-compression" of them when you hit a pothole or roll the body into a curve that weakens them.

The only problem with some mags is that when they are left loaded forever to max capacity, the feed lips can deform due to the constant pressure. Most metal mags or polymer mags with a metal lining would be fine, it's the plain plastic mags that could end up with problems in the long run, that is why Magpul designed those covers for their AR mags that keep the pressure off of the lips.

I leave most of my mags for the weapons that I most often use full all the time.

[lucky-gunner]

+1 39flathead - rep added

I have AR magazines that have been loaded in an ammo box for almost 10 years now. I will randomly pull one out every once and a while just to function test. Never had an issue.

Like 39flathead said though you can have issues with the feed lips over a long period of time. Due to that I only keep my HD/SD firearm magazines loaded, and the aforementioned AR magazines.

[bac0nfat]

Coil over strut springs on a 2000lb car are semi-compressed all the time, it's the constant "unloading & over-compression" of them when you hit a pothole or roll the body into a curve that weakens them.

The only problem with some mags is that when they are left loaded forever to max capacity, the feed lips can deform due to the constant pressure. Most metal mags or polymer mags with a metal lining would be fine, it's the plain plastic mags that could end up with problems in the long run, that is why Magpul designed those covers for their AR mags that keep the pressure off of the lips.

I leave most of my mags for the weapons that I most often use full all the time.

Even the PMags will be fine. I've heard that magpul just made those dust covers because there was demand for them, and to keep the paranoid people happy. I keep all my PMags loaded 24/7 without the covers, and I haven't had a single problem. But PMags are made out of a different material than a lot of the cheap plastic mags out there. If we're talking about Promag or something like that, then YES the feed lips can be damaged with pressure.

[Waldershrek]

They will be fine. They wear out from thousands of cycles, not constant pressure.

Exactly. Repeated cycles of loading and unloading is what weakens the springs.

[39flathead]

Even the PMags will be fine. I've heard that magpul just made those dust covers because there was demand for them, and to keep the paranoid people happy. I keep all my PMags loaded 24/7 without the covers, and I haven't had a single problem. But PMags are made out of a different material than a lot of the cheap plastic mags out there. If we're talking about Promag or something like that, then YES the feed lips can be damaged with pressure.

You may well be right, but I can tell you that if you use a MIC and measure the side of the lip area of an unloaded VS. loaded PMAG, there will be signs of pressure in that area.
And I really can't see why one wouldn't use the covers since they are "free" with the purchase of the mags, but to each his own.

I have nothing against PMAGs, I own a couple dozen of them and have never had a problem, but if they developed a cover only to satisfy the paranoid people, thus wasting money on something unnecessary, the people running MAGPUL are idiots.