Is keeping a large capasity mag full result in failure to feed?

[BigFatKen]

I read that a mag spring getting weak is the most common thing to give a failure-to-feed issue in an autoloader.

I read some writers say to only keep a revolver near your bed while your large capacity magazines should be kept empty with one in the chamber and the rest nearby but loose.

I bought a s/s Mitchell Luger knock off that did not feed properly. Since the mag well is an extreme angle, I assumed weak springs in the 20 year old gun. My gunsmith told me springs were good but the tiny dings in the s/s mag were the problem and likely were bad from the factory. He fixed it and I then found new blued mags for less than his minimum charge.

This was never taught to me in the Army but I never actually fired a whole mag until it was dry. I cannot say if it is true or not. It smells like being overly picky to me.

 

[rcmodel]

No truth to it at all.

Springs wear out from cycling, not from staying compressed.

If you are still concerned about it?
Download by one or two rounds in hi-cap mags.

rc

 

[BigFatKen]

thank you

Thank you. That confirms what I did learn in the Army. An M16 mag can actually hold 21 in an 20 round mag but its tight and we were told not to do that.

 

[230RN]

....

 

[Sunray]

Springs do not lose temper from being compressed. The bends in a flat spring(mag spring) can get work hardened over a long time and crack, but a coil spring won't.
Your Mitchell most like has a poor mag or the lips got bent in a bit. Easily fixed with needle nosed pliers. Tweak the lips open a tick. Mind you, Mitchell stuff is decidedly low end kit.

 

[BSA1]

I have replaced the springs in most of my magazines with Wolff 5% XP for a little added insurance. The Luger is in a class all to itself .

 

[BLB68]

This was never taught to me in the Army . . .

Yep, when I was in the Army, we kept a lot of fully loaded magazines stored for years in sealed ammo cans in our arms room. Just in case the cold war went hot.

 

[Zach S]

Most guns, no.

I use modified Para P14 mags in my Polymer Kimber (BUL M5), it used to go eat magsprings like candy. I started loading to 13 rounds, and have used the same springs for years. Mecgar Para mags were one short on capacity for a while, dont know about now. I think that 14th round compressed the spring too much.

Otherwise, I only download for certain reasons on certain guns. I think the GSG5 I sold held 22 rounds, I loaded 20. My AR22 mags hold 27 I think, I load to 25. Even numbers, four mags to a box of minimags...

USGI mags for my AR are loaded to 28 rounds so they're easier to seat on an open bolt. The same with my few PMags to avoid another ammo shower, due to the lips stretching. The first time I tried to stuff a PMag with a cover in the magwell, was the last time I used a cover...

 

[jim243]

No

Jim

 

[Twiki357]

If they went bad under a constant full load, my 13 round Browning HP mags would be in trouble. They sat fully loaded during 20 years of marriage and kids in the house. They functioned fine at the first range trip and still do.

 

[Sebastian the Ibis]

I find it easiest to load a full mag, chamber a round, holster and go. This is primarily so that I don't have to worry about the extra round when I unload, I just pop it back in the mag. However, it also has the effect of keeping only 14 rounds in the mag instead of 15 99% of the time.

 

[lxd55]

nope. good to go, lock and load.

 

[rcmodel]

If they went bad under a constant full load, my 13 round Browning HP mags would be in trouble

That ain't nothin!

I bought some WWI 1911 mags at an estate sale that were fully load with 1917 head-stamp ammo in them.

They work as well in 2014 as they did in 1917.

I also bought a 1936 Colt Woodsman pistol from an estate with two mags loaded with pre-WWII copper case .22 ammo in them about 10 years ago.

They still work just fine too.

I have several 20 round M-16 mags I stole in 1970 when I got out of the Army.
Again, fully loaded all this time, except when i use them up & reload them for storage again.
And still working fine.

rc

 

[1911 guy]

I remember reading just a few years ago about a German magazine fed machine gun or rifle that was found in an abandoned building. It was loaded, albeit a bit corroded. It was cleared, cleaned and fired. Magazines were reported to function just fine after sixty-plus years of being compressed. I seem to recall it being in a barn loft. Don't remember what country.

 

[Drail]

I thought the OP's question was high capacity magazines? There seems to always be a strong belief when this subject comes up that just because a person has never seen a magazine spring fail from over compression - then it's not possible. I have seen high cap magazine springs fail from over compression and long term compression.

 

[mgmorden]

I use modified Para P14 mags in my Polymer Kimber (BUL M5), it used to go eat magsprings like candy. I started loading to 13 rounds, and have used the same springs for years. Mecgar Para mags were one short on capacity for a while, dont know about now. I think that 14th round compressed the spring too much.

Possible, but its still the repetitive compressing and uncompressing that did the damage to those springs. Loading it there and leaving it wouldn't damage it anymore than loading it and immediately shooting it.

For the most part load it up. The only reason I sometimes download my high caps by a round is that for certain guns a full mag doesn't like to seat well with the slide closed. If that's an issue loading to capacity - 1 can make for a smoother reload. If your gun/mags isn't sensitive to this then I wouldn't bother.

 

[1911 guy]

Drail, I have seen magazine springs fail, too. But they all have one thing in common: Junk spring material and cramming ten pounds of crap in a five pound bag. Cheap "knock-off" mags will fail whether they are high cap or not. Mags that try to cram in extra rounds without altering spring design or length will fail.

Cramming in those extra rounds means over compressing. Taking anything outside its intended parameters results in failure sometime. Junk spring material is self explanatory.

 

[wally]

I use modified Para P14 mags in my Polymer Kimber (BUL M5), it used to go eat magsprings like candy. I started loading to 13 rounds, and have used the same springs for years. Mecgar Para mags were one short on capacity for a while, dont know about now. I think that 14th round compressed the spring too much.

Matches my experience too, exception to every rule, but the Para P14 mags seem to be a marginal design and very hard on the springs when loaded to full capacity. Well designed and manufactured mags don't have this issue.

 

[Drail]

1911 guy, I agree with everything you said and have in the past posted essentially the same thing you said. A problem though, is that no one seems to know if they have one of these junk springs. Unless you replace your factory spring (most of which ARE junk springs from the lowest bidder) with high quality springs from a company that actually makes springs (Wolff or ISMI) you don't know what you have. So what happens is everyone just keeps repeating the tired old mantra - "springs only wear out from use - not compression". While partially true it's just a little more complicated than that (like most of the "wisdom" on internet forums). Double stack high cap magazines suffer more from overcompression than single stack magazines from being fully compressed for long periods of time. If you are using a high cap magazine (including an 8 round .45 ACP flush fit single stack), downloading the mag takes a lot of stress off of the spring. I urge everyone who "needs" to keep their magazines fully stuffed all the time to buy some good springs for them. If the last two rounds don't feed as perfectly as the first two then you're on the ragged edge of having a feed stoppage. Almost every customer I have ever had who brought in a gun with last round feed problems were amazed when all I did was sell them a new Wolff extra power spring for their magazine and suddenly the gun ran perfectly. So the bottom line here is that keeping high cap magazines stuffed all the time may not necessarily cause it to fail - but it should be given some consideration. I am sure that when Browning looked at his original 7 round magazine he may have pondered trying to get an 8th round in there and decided not to because he realized the spring would probably not last very long when compressed that much. Cramming ten pounds of crap in a five pound bag is absolutely right.

 

[fletcher]

Yes, the springs certainly can weaken over time (causing failures to feed), and there are several threads containing explanations of how and why this happens.

However, a quality spring will have been designed to account for long term compression and won't have any issues. Note that even good springs take some finite amount of set - they've just been designed so that it does not adversely affect function.

Personally, I keep my mags stored loaded to full capacity (single stack, double stack, pistol, rifle) and have never had a problem.

 

[Drail]

Yet. Keep those fingers crossed.

 

[Baron66]

A quality spring, built without defect, can be compressed and uncompressed hundreds of thousands or millions of times before failing. A spring can also be left compressed without causing issues.

What DOES cause premature failure is a spring being compressed too much. For example, a spring can be compressed to 90% many times but, if you're compressing it to 95%, it will fail prematurely.

That's where the magazine design comes into play. A well designed magazine will not overcompress the spring. Ever see a mag that can almost fit another round? That's the extra room they engineered into it to keep the spring from being overcompressed.

So, you can use a quality magazine however you like. The spring will get a little softer as it breaks in but it should not fail in your lifetime.

Older magazines are a different story. Magazine design and spring technology is alot better today that it was even fifty years ago. In older mags, load one less than the max and you should be good to go.

 

[X-Rap]

I believe over compression is a valid concern as well as poor quality in some brands.
There is a booming spring business in the shooting world and it's not just because of some being falsely concerned with failures.
As has been stated, many failures of good weapons are the result of bad mag springs and I doubt that all of those shoot enough to be wearing out good springs due to cycling of the springs.
I personally do keep a certain limited amount of mags loaded but could never get the idea some have of loading all they have.

 

[buck460XVR]

All Lugers, even the originals, were picky about mag fit and spring tension because of the toggle action design. Thus it's no surprise that a damaged mag would cause problems in the Mitchell. BTW...the Mitchell's were suppose to be a pretty decent firearm.

 

[RustyShackelford]

Semi auto pistols....

Most modern semi auto pistols can be safely used with fully loaded magazines even if the mags have been in storage for long periods.
You can load/unload magazines but it's not really necessary.
I keep my current Glock 21 .45acp loaded with either 5 rounds of MagSafe SWAT(home defense) or a 10rd clip of Hornady Critical Duty.
I might get a new box of .45acp Critical Duty or Federal HST 230gr +P JHPs for use on security posts. Id then load the magazines with 13rd each.

Note; this post is for well made, modern pistols not off-brand, old-antique, low quality or poorly maintained firearms.
If the springs, parts, etc look sub-standard or low quality then I would not keep the magazines fully loaded.

RS