Magazine capacity and lengthy storage

[matthewb0051]

Crap title but I couldn't think of anything else.

When I was a trigger puller the conventional wisdom was that you didn't want to leave 30 rounds in your mags for any real extended time because it would compromise the spring. No idea where we came up with that logic but there it is. It may have just come from the E-4 mafia but IDK.

So I wanted to ask the group whether anyone has actual knowledge on this quandary or whether anyone else has heard of this 'wives tale'. Same question for pistol mags.

The belief has stuck with me so much that if I were to have 30 round mags now, I would only put 20-25 rounds in them unless I was going to the range.

[vash]

My brother gave me his work pistol when he moved onto the newest version.

When i got it, it had seen decades of service use. Magazines fully loaded 24/7 for the most part. My brother told me the springs were weakened (or developed memory?). it was true, it didnt always feed the next round.

I bought aftermarket springs and it's all good. I keep them fully loaded again, for the most part. The springs were not expensive.

[masraum]

I've heard that a spring shouldn't stop springing as long as it's not deformed past it's limit. That was a response to this exact question, can mags be left full without the spring dying.

[Seahawk]

Always an interesting discussion, one of the reasons I have a revolver as my NS gun.

My father was Army and always rotated his magazines from loaded to empty every few weeks. He had a minimum of three magazines for his Colt LW Commander: two were always ready, one "resting".

The current guys I know say it doesn't matter...some even say the loading and unloading causes more wear and tear. I stick to my Dad's regime for no other reason than it is what he, Bob, did.

I have a Ruger MK II Bull Barrel I bought in 1983 and the three mags all work like champs, same with my Dad's 1952 Colt Commander.

Funny how that works.

The 30 round mag discussion is moot to me. All my stuff stays empty. We probably have 20 magazines that I load only when we shoot.

[matthewb0051]

Originally Posted by Seahawk

The current guys I know say it doesn't matter...some even say the loading and unloading causes more wear and tear. .

Yes it does... to my fingers and hands

[Flat Six]

Originally Posted by matthewb0051

Crap title but I couldn't think of anything else.

When I was a trigger puller the conventional wisdom was that you didn't want to leave 30 rounds in your mags for any real extended time because it would compromise the spring. No idea where we came up with that logic but there it is. It may have just come from the E-4 mafia but IDK.

So I wanted to ask the group whether anyone has actual knowledge on this quandary or whether anyone else has heard of this 'wives tale'. Same question for pistol mags.

The belief has stuck with me so much that if I were to have 30 round mags now, I would only put 20-25 rounds in them unless I was going to the range.

Originally Posted by masraum

I've heard that a spring shouldn't stop springing as long as it's not deformed past it's limit. That was a response to this exact question, can mags be left full without the spring dying.

Originally Posted by matthewb0051

Yes it does... to my fingers and hands

Good timing; I saw this just the other day -- 17 years:

[id10t]

Springs wear as they expand/contract. So leaving a mag loaded? No issue, at least for the mag.

Storage conditions COULD be issues for the ammo in the mag though.... or possibly also the mag depending on what it is made from (there is a video out there of a cheap ProMag deformign in the summer sun out west)


That said, I've fired a full mag w/o issues from a Glock that was left loaded for 10-11 years, and five mags for a Ruger Mk II that were left loaded for close to 20 years - but they were stored in my bedroom closet. Glock mag I gave to a friend and I think it is still going strong (been a few years since I've seen him) and the Ruger Mk II mags are still kicking and get to eat a few boxes per range trip.

[gacook]

Originally Posted by matthewb0051

Crap title but I couldn't think of anything else.

When I was a trigger puller the conventional wisdom was that you didn't want to leave 30 rounds in your mags for any real extended time because it would compromise the spring. No idea where we came up with that logic but there it is. It may have just come from the E-4 mafia but IDK.

So I wanted to ask the group whether anyone has actual knowledge on this quandary or whether anyone else has heard of this 'wives tale'. Same question for pistol mags.

The belief has stuck with me so much that if I were to have 30 round mags now, I would only put 20-25 rounds in them unless I was going to the range.

Don't have a real answer, but I operate under the same logic as you. I only keep 20-25 in my 30 round mags, and only keep 15 in my 17 round pistol mag.

I DO keep 9 in the 9 round mags, though...

[matthewb0051]

Originally Posted by gacook

Don't have a real answer, but I operate under the same logic as you. ..

Were you part of the E4 mafia?

[gacook]

Originally Posted by matthewb0051

Were you part of the E4 mafia?

For a short while, at some point in history...

[Racerbvd]

I only load half capacity for ones that don't get fired often.

[Por_sha911]

Physics and metallurgy will tell you than a spring weakens from being exercised. Compression but without movement will not weaken the spring. Unless the spring is stressed beyond its limits, there is no harm. I seriously doubt a full mag is beyond the limits.
As an example. If you have a new magazine and the spring is too tight, you can leave it fully loaded for a week with no change but if you take a dowel and compress the follower between full and empty 1-200 times the mag spring will have a manageable amount of give. I did that for a new G43 where the type 2 springs were notorious for being so tight you couldn't load the last round into the mag. I used a wooden dowel and after a couple hundred compressions it worked fine.

[svandamme]

a spring does not care about being compressed or decompressed
it only cares about total cycles, exercise indeed

There is such a thing as spring creep where it changes and loses some strength under load, but that happens fast and early on in its life and then halts to pretty much nothing. Think 2% reduction which in the scope of a magazine is irrelevant because a good mag spring has surplus spring power built in to it.

it is a non issue.
your more likely to have another with old ammo(defo if reloaded or commercial and not military ammo) kept for years in a mag, in a cupboard (non sealed athmospheric) then from the spring..


The only thing I would do for long storage and real must work
is load -1 of max capacity, for the simple reason of not having any FTF from things binding to much due to some kind of sticky grease in the mag or oxidation or other metal to metal reaction
More an issue on metal mags then polymers, Think M14 mags and old DAG nato surplus ammo ( the kinda that had cardboard glue corrode the brass not exactly SHTF material)