Mag spring integrity - loaded vs. unloaded

[JohnKSa]

Take an old spring type bathroom scale, zero it and place a 100 lb weight on it and walk away.

About how long do you think it would take for the scale reading to increase to 110 lbs?

It sounds like you have experience with scales that are properly designed and that don't overstress the spring.

On the other hand, if the spring was only designed to handle weights up to 75lbs because the scale designer decided to make the scale lighter/cheaper/smaller and therefore picked a spring for the scale that was overstressed by 100lbs of weight then your scenario could certainly play out.

Part of the problem with this topic is that the "springs don't weaken" crowd seems to think that the "springs can weaken" crowd is actually the "EVERY SINGLE SPRING ON THE PLANET NO MATTER ITS APPLICATION OR DESIGN WILL ABSOLUTELY WEAKEN!" crowd.

Therefore they believe that if they find 1 spring, or even several springs that don't weaken they think they've proved their point.

I know that some manufacturers are using 303 stainless for springs.
303 can not be heat treated for spring properties, and making the spring work-hardens the stainless enough that it has spring properties. These are not properly made springs, IMO.

The point is largely moot.

Regardless of WHY, it seems that we all agree SOME magazine springs DO weaken from being left compressed or from being cycled.

Not ALL, but SOME.

Therefore it makes sense to be aware of the fact that this CAN be a problem (not that it WILL be a problem for EVERYONE) so that it doesn't take us by surprise IF it does happen to be an issue with a magazine we own.

[Sport45]

I'm really a fence-straddler in this argument. In the bathroom scale example I made above I imagine that in time the spring probably would stretch (or compress, depending on the scale) until the pointer indicated a higher weight. I have no idea how long that would take.

When you buy bearings you have a pretty good idea how long they will last because they are rated for purpose. Firearm springs seem to be something of a crapshoot since there don't appear to be any industry standards for life expectancy. Anybody can put any spring in a package and sell it. They can even put a cheap spring in a package and sell it with a lifetime guarantee knowing that 90% of their customers won't bother trying to return it.

Grandpa's 1911 had a 7-round mag. When the follower bottomed out teh spring was far from being stacked and a loaded mag could reasonably be expected to work when pulled out of storage 50 years later.

Someone saw that same mag and thought, "Hey, there's room for another round in there if I reduce the height of the follower." So they made a shorter follower and loaded an extra round by compressing the spring an extra half-inch or so. This extra stress may be the difference between a loaded mag lasting 50 years or only 5 years before it fails to function.

Back in the day we didn't have computer models and such so pretty much everything was designed with a much larger "safety factor" than it is today. Metal was thicker than it needed to be and springs weren't close to being overstressed.

[Walt Sherrill]

Someone saw that same mag and thought, "Hey, there's room for another round in there if I reduce the height of the follower." So they made a shorter follower and loaded an extra round by compressing the spring an extra half-inch or so. This extra stress may be the difference between a loaded mag lasting 50 years or only 5 years before it fails to function

Hmmm. Extra space.

For my CZs and CZ clones, I have a bunch of 10-round mags that I've used for IDPA competition. They're cheaper than 15 or 16 rounders, and the limit in IDPA is 10 rounds.

The springs used in the 15/16 round mags are exactly the same springs as are used in the 10-round mags. While there have been a bunch of different mag bodies available from the CZ factory over the years, some of these mags are sometimes identical, except for indentations in the sides of some of the 10-rounders that keep the follower from going lower in the tube.

If a set of the indented mags are loaded to 10-round capacity, and another set are loaded to 16-rounds, and then stored for a long period, they have the same springs but different loads. According to the technical materials we've seen presented, and to the testimony of several of the folks who work with the spring steel involved, there should be a difference in the performance of the two sets of springs over time. It may be trivial and of no consequence, but there will be some sort of change.

Will the more-highly stressed 16-round mags fail? Perhaps not. Probably not. Will those springs perform exactly like the 10-round springs? Probably not. Will they still function as well as the 10-rounders six or seven years from now. I seriously doubt it -- but haven't run that test, and am not likely to.

Nobody has explained why the springs in my 8 Kahr compact mags failed as quickly as they did. They would not function -- the gun would not chamber rounds. These were factory mags with factory springs. When replaced, the gun functioned properly.

There was no change in the gun itself; the slide to frame fit had not changed; the chamber size was the same; the ammo used was the same. The springs had no breaks that could be discerned. They old springs were much easier to depress than the replacement springs. MUCH easier.

I don't think my experience with these mags is so unusual that we must say these particular eight mags are some kind of technical oddity. I've heard of similar problems with other guns, but not with so many failing at the same time. I didn't keep those mags loaded, but the prior owner might have. For sake of discussion, let's ignore the fact that all of them stopped functioning correctly at about the same time, and say that only two or three did so. What caused just two or three to stop working properly? As I said: none were obviously broken. Explain why these "compact" mags failed.

The technical materials presented here explains the theoretical reasons for possible failures. They are interesting links, and even when they are shown on Wikipedia, there are citations of their original technical sources -- so it's hard to dispute their technical relevance. The claim that mags won't fail if properly made and designed only tells us that mags SHOULDN'T fail; but, as stated, that claim has no real definition and is essentially meaningless -- it's a statement of faith, and little more. I'd like to believe it was true, but belief isn't the topic, here.

Why do some of these springs seemingly wear out? We know that many other springs will live long, useful lives and never inflict a failure on the original (and maybe subsequent) owner. Was it an owner malfunction? Or have the springs done exactly what they were intended to do, over their intended life, as the designer meant them to?

.

[danez71]

Walt,

I'm not very familiar with Kahrs...


Is what happen to you some what common.... do you hear of it much with Kahrs?

And could you briefly describe the scenario again (how long loaded or not, round cound/mag estimate).



I'm guessing at this point.... either bad batch of springs or Karh is ok with that life span.

I do believe that some of the mfg are making the decision to accept shorter spring life as a trade off in some of their designs.

[wildbill22]

Gentlemen , I have read all your replies and have not noticed an answer but very knowledgeable debating. Any conclusion to a magazine of a mouse size gun, a beretta 950 bs jetfire or a iver johnson tp22 ? I haven't kept score but it sounds like magazine full less one round is the best ? Please correct my assumption if needed . Thanks for all your input , your time and effort . So far it has been a very educational experience - wildbill22

[JohnKSa]

I have read all your replies and have not noticed an answer but very knowledgeable debating. Any conclusion to a magazine of a mouse size gun, a beretta 950 bs jetfire or a iver johnson tp22 ? I haven't kept score but it sounds like magazine full less one round is the best ?

Good quality, standard capacity, single stack factory magazines seem to be the least likely to be affected by this problem.

My "answer" to this problem is as follows.

First of all, I don't recommend taking any remedial action as a blanket solution unless you have some information that suggests your particular firearm is prone to this issue. If you have either experience or research evidence that indicates that your model of firearm is known to have issues with springs weakening then you may want to take the precaution of downloading by a round or two. Otherwise, I would wait until you have evidence of a problem before taking any action to eliminate the problem.

In general, I would say that all you need to do is:

1. Be aware that magazine springs can wear out over time from use or from being left loaded. This is the big one as far as I'm concerned. The rest of the process follows logically from accepting this statement.

2. Given that there is a possibility that a problem could develop, gun owners should check their equipment periodically to make sure that it is working properly. If a problem is noted then take remedial action. Either replace the springs or the magazines.

3. Continue checking the equipment periodically to make sure that it is working properly. If the problem recurs then take remedial action again but from that point on I would recommend additional action since the problem seems to recur. After the tendency to recur is demonstrated I would recommend either adopting a periodic replacement strategy to prevent a failure when a failure would be, shall we say, inconvenient, OR downloading the magazine by a round or two. It seems that either approach is equally likely to be effective in preventing a recurrence and each has different advantages/disadvantages to weigh.

Back in the day we didn't have computer models and such so pretty much everything was designed with a much larger "safety factor" than it is today. Metal was thicker than it needed to be and springs weren't close to being overstressed.

I work at a company that does aircraft modification. The base aircraft we use most often were manufactured in the 1960's. We have looked at using newer aircraft but it turns out that the older aircraft were pretty impressively overbuilt for exactly the reason you mention. Without the availability of computer modeling to precisely determine stresses and corresponding manufacturing requirements, the designers simply built everything stronger than they needed to.

To use a newer aircraft, we found we would have to go through the entire airframe and cabin and reinforce it extensively to deal with the additional stresses. It turned out to be a much better option to simply continue refurbishing and maintaining the older aircraft.

[Walt Sherrill]

Walt,

I'm not very familiar with Kahrs...

Is what happen to you some what common.... do you hear of it much with Kahrs?

And could you briefly describe the scenario again (how long loaded or not, round cound/mag estimate).

It's not a problem that I've heard other kahr owners complain about. I don't think my experience was typical. I cited the Kahr problem because it was a recent, real-world example. I suspect the mags I got with the used gun had been used and abused a good bit before I got them, but they worked quite well for quite a while AFTER I got the gun.

I (and others) have had similar problems with other mags in other guns. It doesn't happen that often, but does happen often enough to think there's more at play here than just a bad batch of springs. In several years of acting as a Safety Officer in IDPA matches, I know I'll see mag-related problems a couple of times a year, and mostly in folks new to competition.

The Wolff Springs company website (WWW.GUNSPRINGS.COM) has a very informative Frequently Asked Questions area that suggests downloading hi-caps (and compact mags) a round or two when storing them loaded to extend spring life. They tell us that when mag springs are stressed to (or near) their design limits the springs can degrade.

In the Kahr example I cited, the rounds simply wouldn't chamber. They weren't lifted high enough to be caught properly by the slide. I had a similar problem a few years ago with some South African mags for Browning Hi-Powers, bought from CDNN. They were supposedly new mags. After about a year or two of limited and intermittent use, the nose of the rounds in the mags would dip, the springs seemed to lose their resistance, and the mags just wouldn't work. (I've still got the mags, somewhere, but nobody I emailed at Wolff could tell me which springs I should use as replacements. I may try some CZ mag springs, one of these days.)

In other gun forums, I hear of horror-stories about mags, and a common response seems to be: "I tosssed the damn things and bought some new ones." That'll certainly work, but it's an expensive solution if the problem is just a spring gone bad. This last set of BHP mags may have had inferior quality steel springs, or maybe someone slipped in some used ones disguised as new -- but there are a lot of these same mags in use, and I've never heard any complaints.

I don't think mag failure is a common problem, but I do think that spring problems can be made less common by doing some of the things mentioned here and on the Wolff website. And you only need the problem to happen once, when it matters, for it to go from being a pain in the butt, to being a BIG TIME PAIN IN THE BUTT.

"Well-designed, well-made springs" is an almost meaningless term. Nobody can define exactly what it means. I've had gun coil springs fail that didn't break, and they were from reputable companies for high-quality guns. I've had far, far more that never seemed to degrade in any way.

The technical specialists involved in this discussion say that BREAKAGE is the final phase of spring failure, but creep (lack of extension) and other forms of weakening comes first. I think that most gun owners toss or replace springs before they can break, as they quit working long before they'll break.

I don't think we have an definitive answer to the questions presented here. I do think that stretching springs -- which was addressed in a different message chain -- is probably not good; but one participant in the other string of messages swore by that practice. I also think that downloading compact/sub-compact, or high-cap mags a round or two when stored loaded is probably a good idea.

I also think that gun designers, nowadays, are using springs in ways that weren't even considered in times past -- and our expectations of spring life may have to be adjusted as a result. And as JohnKSa notes, in a prior message, folks may not OVERDESIGN as much as they used to.

If you only have 10-round 9mm mags, 7-round 1911 mags, or only shoot full-size guns with standard size barrels and recoil springs, none of this discussion may matter, as you're probably not going to encounter problems.

If you've got a modern sub-compact in 9MM, .40 or .45, with a very short barrel, or if you are running a gun with 15 rounds of 9mm+ ammo, you may see some failures. Don't be surprised.

When I first got a Glock 17 and later a 34, I was really impressed with the fact that they could stick 17 rounds in those mags. But I'm even more impressed with the fact that the Glock 35 holds 15 rounds of .40 ammo in what is basically the same mag. That's really a lot rounds in the space available. There's hardly any space left in those mags for springs. Those springs are really compressed when the mag is fully loaded.

Reread the various technical sources suggested by some of the other participants, and make your own decisions.

[microtech]

i own a USP Compact in 9mm and i have 3 mags that i have kept fully loaded with JHP ammo since day one. I have had it for almost two years now, and i go to the range about once a month and have never had a problem yet. I took apart my mags to clean them a month ago. The springs were out and fully expanded for about an hour each and when i put them back in, i noticed that the mags were stiffer. So, all in all, i think a lot of mags are very resilient and will last for many years if not more.

[Bill DeShivs]

Here is a thought-
Perhaps some magazine followers are short-allowing the user to bottom the springs out trying to load that "extra" round, or they just loaded until the mag wouldn't accept any more.
Many magazines have a "leg" on the follower that will not allow the springs to be over compressed.

[JohnKSa]

So, all in all, i think a lot of mags are very resilient and will last for many years if not more.

I agree. I would say that most magazines will last indefinitely. It has never been common to hear of magazine springs giving out, and in the last few years I would say that the situation has improved.

Seems like the biggest spike in occurences happened during the early part of the "wondernine" era when manufacturers were competing to squeeze every last bit of capacity out of their magazines to keep up with (or surpass) the competition. Even then it wasn't what I would call common.

But it does still happen occasionally so it's important to be aware of it.

Many magazines have a "leg" on the follower that will not allow the springs to be over compressed.

Most of them do in my experience. But not all of them.

[danez71]

Just to hit on a few thing from the last few posts.

I'm a firm beliver that people are not over designing things like the used to. Its a waste from a company profit stand point and we are a capitalist society.

I USED to be impressed with how many rounds companies were able to stuff into those smaller guns/mags until several years ago.

The Kel-tec size guns started peaking my interest and I started reading more about "jams" etc (nothing against kel-tecs... not necessarily mag related).

Thats when I light bulb went off. Just like everything else in life, EVERYTHING has a trade off.

And I'm OK with that. Sure, Id like everthing perfect and for free but thats not realistic.


Along the lines of what Bill said.... and JohnKSa may have elaborated on more.

There was/is a growing demand for smaller guns. Gun mfg's try to out do each with smaller guns... and then even smaller with more round capacity.

Consumers have bought everything that hit the shelf for the last decade or so (overstating but you get the idea).

'New Product Introduction' has equaled increased sales and 'Market Share'.


However, lets not forget, EVERYTING has trade offs.


Some might be puzzled to hear.... this issue has not been a problem for me in the big picture.

Sure, springs do get weaker, softer or call it want you want. There's no way around it. But it really isnt a problem until your gun doesnt work right. Right?

So, its really very simple... check your 'stuff' every now and then.

[barret_munkey]

I woundered this too , in my g19 mags the last round really needs to get pushed in there with some force so I dont load it just in case it did cause damage, ima keep playing it safe though