Just curious if you keep the mag loaded for any length of time how long before it looses it's tension? How often should you replace springs? I had an old Norinco I traded off that I kept 2 mags 1/2 loaded. Probably that way for years. I just don't want to cause issue with some of the new pistols I have acquired. But don't want to be unprepared if the need arises. Have a revolver next to the bed, loaded, not an issue. But picked up a semi auto for a car gun. Don't want feed issues from the constant tension and heat in the car. Thoughts and thanks.
How long will a mag spring hold up if left loaded?
- Thread starter xmen
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There will be many replies bemoaning that this subject has been brought up again, there will be many replies saying load your mags and dont worry, there will be a few replies saying don't leave your mags loaded, some folks who are engineers will reply and explain how springs work.
My advice, if its a 7 round 1911 magazine don't worry about leaving it loaded, if its a Ruger SR9 17 round magazine it will probably be fine, but if it makes you feel better just leave a few bullets out.
My advice, if its a 7 round 1911 magazine don't worry about leaving it loaded, if its a Ruger SR9 17 round magazine it will probably be fine, but if it makes you feel better just leave a few bullets out.
Thanks, i'm sure it has been covered but I did do a search and did not see this topic. Tough when it just picks key words. I just did not know if there is a general rule of thumb. Nothing I saw in the manuals either. The manufacturer might have the answer too if I call customer service. But not sure if all springs are created equal. You can buy a $19.00 mag and you can buy a $60.00 mag. Depends on the maker.
Captains1911
New member
Just google it "leaving magazines loaded."
I have some 30 rd pmags that have been loaded with 30 rds for over 7 years now and still function flawlessly. I have several glock mags that also stay loaded most of the time and work perfect.
I could get into the science behind it but I'm tired. Bottom line is, it's the multiple loading and unloading cycles that fatigue steel springs, not sustained compression.
I have some 30 rd pmags that have been loaded with 30 rds for over 7 years now and still function flawlessly. I have several glock mags that also stay loaded most of the time and work perfect.
I could get into the science behind it but I'm tired. Bottom line is, it's the multiple loading and unloading cycles that fatigue steel springs, not sustained compression.
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What wears out springs is an effect called hysteresis. Simplified, it is caused by the repeated loading and unloading of a spring. Just loading the spring and leaving it that way doesn't wear it out, as long as it is within the design limits of the spring.
So don't worry about it, just load it up and keep it that way.
So don't worry about it, just load it up and keep it that way.
IMHO, it also greatly depends on the quality of the material in the spring.
Truly, one of those you get what you pay for.
A high quality firearm shouldn't have a problem. Think of all those cops carrying ammo loaded in magazines 24/7/365.
On the other hand, if you buy a cheap 3rd world copy of a copy knock off... you really don't know what you are getting.
And as a side note.... I have some Colt AR mags that have been loaded fully for over 30 years... and have functioned every time I have checked them. They are the ones that came with the rifle.
Truly, one of those you get what you pay for.
A high quality firearm shouldn't have a problem. Think of all those cops carrying ammo loaded in magazines 24/7/365.
On the other hand, if you buy a cheap 3rd world copy of a copy knock off... you really don't know what you are getting.
And as a side note.... I have some Colt AR mags that have been loaded fully for over 30 years... and have functioned every time I have checked them. They are the ones that came with the rifle.
I had a glock 17 magazine loaded with 16 rounds (one less than max) for 19 years. I basically forgot about it in 1991, then discovered it in 2010. It was loaded with Remington 115 grain +p JHP. I took it to the range and it worked perfectly and all the ammo fired... and I still use it today.
Brotherbadger
New member
Bingo.
I inherited a Sig from my grandfather. It came with 3 mags: 2 factory mags and a ProMag. Guess which one always gave me problems? The cheap promag. I threw out that Promag after the first range trip(i actually didn't look at the mags until i kept having problems). Don't buy bad quality mags and you avoid issues. Problem solved.
To OP: Keep the mags loaded if you want. It won't harm anything.
Springs won't wear from being compressed as long as that compression is not being their elastic limit. Poorly made springs and mags that attempt to fit 17 rounds in a 15 round body can certainly have issues just from compression.
In the end, it probably comes down to who designed and constructed the mag and spring. Factory Beretta, Swiss Sig and HK mags have been amazing in their longevity and consistency. HK still limits flush mags to 15 rounds, which I think is a hint.
Those Norincos were really premium in many ways, and 7 rounds is conservative. At worst, you'll someday need to spend $3 on a spring.
In the end, it probably comes down to who designed and constructed the mag and spring. Factory Beretta, Swiss Sig and HK mags have been amazing in their longevity and consistency. HK still limits flush mags to 15 rounds, which I think is a hint.
Those Norincos were really premium in many ways, and 7 rounds is conservative. At worst, you'll someday need to spend $3 on a spring.
Jim Watson
New member
As said, a GOOD magazine spring will retain adequate tension for a long long time.
But a cheap one or an attempt to increase the capacity without more spring space will not.
I think the problem is that all the mechanical engineering stuff you read about springs is based on small deflections, while a magazine spring is deflected a lot, and gets beyond the theoretical.
But a cheap one or an attempt to increase the capacity without more spring space will not.
I think the problem is that all the mechanical engineering stuff you read about springs is based on small deflections, while a magazine spring is deflected a lot, and gets beyond the theoretical.
Walt Sherrill
New member
RX-79G said:
What RX-79G said. Glock mag springs seem pretty long-lived, too.
We've had a lot of discussions here on TFL about this topic, with input from some pretty knowledgeable engineers, including one who was a Metallurgist. The "elastic limit" is the key. If a spring, when compressed, is not pushed too far, it'll live a long, long life, degrading very slowly. It'll probably outlive its owner. Think about tappet springs in cars: they cycle many, many millions of times over a car's life. But, they're used in a way that doesn't push them past their design limits. (They are also relatively massive springs for their length.) If cycling alone wore out springs, most of our cars would have to have tappet springs replaced pretty regularly.
On the other hand, if you keep some sub-compact and hi-cap mags fully loaded for long periods, they will degrade. But not necessarily rapidly -- it'll depend on the design of the mag and the work the springs are expected to do. Science and the engineers who have addressed this subject here before tell us that all material under stress, be it glass, rubber, steel, wood, plastic, etc., degrades under heavy load... and the closer the material get to the extreme limits, the faster it will degrade. As others are ready to tell us: there is no free lunch.
Wolff Springs, in its FAQ area, suggests downloading a hi-cap mag a round or two if they'll be stored over long periods. For carry, just load'em and carry'em. The cost of degradation is offset by the greater capacity. I think the same could be said of mags used in sub-compact guns, too. But check those mags periodically at the range to assure that they function properly.
Think about it: a fully loaded mag is still trying to work. A 7-round 1911 mag is pushing those seven rounds up against the mag lips. Those mag springs, however, have a lot of reserve power they're not near their design (elastic) limits.
The same thing happens with the spring in a 10-round double-stack* 9mm full-size mag -- there's still a lot of reserve power in the springs when the mag is fully loaded.
Some 15 - 18 round 9mm mags, however, use the same spring as a 10-round mag, but in the hi-cap mags those springs are trying to lift almost twice as many rounds with when not being used, and does almost twice as much work with each spring cycle.. The same springs (10-round vs. 17 round) aren't doing the same work, and something has to give.
The same holds true for recoil springs in many of the most compact guns: the recommend spring life for a Rohrbaugh R9 is about 250 rounds, although they'll go longer. Why does that spring not last thousands of rounds like the springs in full-size guns of the same caliber? Doing the same work with less spring, or more work with the same spring has a cost.
Note: unloading a mag doesn't make it get better -- springs don't heal. Stretching springs doesn't return them to their prior state, either -- it just degrades them even more; they'll seem better for a short while, and then they'll just get worse.
Rotating your mags isn't easier on your mags or mag springs -- it just spreads the wear over a larger number of mags. If the unused mags are kept loaded, you've gained little by rotating your mags. Unload or down-load those hi-cap mags and you can extend spring life, because when they're unloaded they're not working, and when they're relaxed by a round or two. they are father away from their elastic limits.
*See comments in following messages. "Double-stack" added.
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Jim Watson
New member
I don't know that I would go so far as to say that.
Recall that the original standard magazines for 1929 Super .38 and 1950 Commander 9mm were for 9 rounds. The 10 round smallbores are like 8 round .45s. Unless they have a hidden extension (as many now do), they are cramming a quart into a pint pot and spring life can be short.
Walt Sherrill
New member
You're right: I should have been more clear. I was implicitly addressing full-size 10-round double-stack mags in guns that offer the same size mags with higher capacities. I didn't write that. I went back and changed the origional post to clarify that point.
In the case of CZ 10-round and 16 or 17 round mag, they use the mag tube and the same spring with different followers. In the higher-cap mags, the springs are compressed more fully.
That would not be the case with a single stack gun. But most single-stack mags with extra capacity are larger mags, and not the same. The fact that the mags springs you cited had shorter lives was the elastic limit issue.
In the case of CZ 10-round and 16 or 17 round mag, they use the mag tube and the same spring with different followers. In the higher-cap mags, the springs are compressed more fully.
That would not be the case with a single stack gun. But most single-stack mags with extra capacity are larger mags, and not the same. The fact that the mags springs you cited had shorter lives was the elastic limit issue.
I've had a Wilson Combat 8rd .45 mag loaded continuously for twenty years. I take it out and put some rounds through it every couple of years, and it still feeds perfectly.
I do not depend on that mag for anything, and consider the long-term loaded deal something of a stunt. If I were relying on that mag in a duty or defensive weapon, I'd have at least one more, and rotate them if/when they weren't both loaded.
I do not depend on that mag for anything, and consider the long-term loaded deal something of a stunt. If I were relying on that mag in a duty or defensive weapon, I'd have at least one more, and rotate them if/when they weren't both loaded.
Jim Watson
New member
The 10 shot AWB neutered double column magazines are difficult to work with. Since they had to gain BATF approval, most are very tough to load the tenth round and spring loads can be strange. I have not seen one differing only as to the follower, most had tube modifications to restrict capacity.
Walt Sherrill
New member
Not all of them are difficult to work with.
I've seen at least three variants over the years. Some CZ 10-rounders have laser cuts that prevent alterations, some have big indentations that limit follower movement, and some had a shortened metal tube with a plastic base that reduces capacity.
When the ban was still in effect, they used that same shortened metal tube with a shorter plastic base for their "compact" CZs. Same spring, same capacity, but overall length was less to allow a flush-fit "compact" mag. (Wolff now offers different springs for the "compact" CZ s, but That wasn't always the case. They don't offer different springs for the 10-round mags or the 13+ mags. I suspect both size mags, 10-round or 10+ use the same "compact" spring.)
If you'll check the Wolff site you'll see that only one spring is available for the the full-size 75/75B models, and spring used doesn't differ with capacity. The same seems to be true for the other CZ-pattern guns like the Tanfoglio and Sphinx guns. What does differ with most of these guns is the follower and, in the case of the even-higher capacity mags, the mag base.
Lots of states still limit mag capacities to 10-rounds, so CZ has to make mags for the 10-round limit states, too. I don't know WHICH style mag is used for new CZ guns in those "limited" states, and hope I never have to find out.
If you'll check the Wolff site you'll see that only one spring is available for the the full-size 75/75B models; spring size doesn't differ with capacity. The same seems to be true for the other CZ-pattern guns like the Tanfoglio and Sphinx guns. What does differ with the CZs is the follower and, in the case of the even-higher capacity mags, the base.
That commonality of spring size also seems to be true of some other gun maker lines that sell double-stack guns that offer both10-round mags and 10+ round mags.
Jim Watson
New member
My only 10 shot CZ magazine had dents to limit follower travel, slits through the front and rear walls of the tube so if you drilled out the dents, the magazine would fall apart, and a regular spring that when compressed had to go bumpity bump past the dents. It was unreliable in feeding. I tried various things like a plug to bring the bottom of the spring up to the dents and load it as though it had the full 15, but that didn't work either.
My only 10 shot Sig Sauer magazine was of the short tube, long base type. It Just Worked so I had no need to fiddle with the spring.
All I ever had for my short affair with a H&K USP were 10 shot magazines with Germanically complex floorplates to limit capacity.
I don't know about taking Wolff as Gospel on springs. I am reminded of the auto writer who pointed out that GM had 25 different fan belts to cover one year's models whereas the parts store only carried five and counted on the adjustment of the alternator mount to get by.
My only 10 shot Sig Sauer magazine was of the short tube, long base type. It Just Worked so I had no need to fiddle with the spring.
All I ever had for my short affair with a H&K USP were 10 shot magazines with Germanically complex floorplates to limit capacity.
I don't know about taking Wolff as Gospel on springs. I am reminded of the auto writer who pointed out that GM had 25 different fan belts to cover one year's models whereas the parts store only carried five and counted on the adjustment of the alternator mount to get by.
