Mystery solved: what are Glock and Wolff magazine springs made of?

[DreadPirateMoyer]

(or at least I hope it was a mystery up until this point, considering I've tried incredibly hard to find citations or sources on what these springs are made of outside of just hearsay and speculation)

Hi there everyone,

For the last 2 years, I've been trying my damndest to find out what Glock and Wolff magazine springs are made of. However, no one seemed to know these spring materials no matter where I asked (including here). Google also turned up nothing other than baseless speculation based on the color of the springs and other unscientific criteria. Even direct calls and emails to Glock and Wolff brought nothing, as neither company was willing to share such guarded technical information about their products. It seemed I was at an impasse.

In desperation, I asked my Facebook friends if they had any ideas, and one of my buddies from engineering school offered to run some SEM (scanning electron microscope) tests for me so we could find out (I'm currently a practicing engineer, and he's pursuing his PhD). Not only did we want to know for curiosity's sake, but we thought it would be fun to solve a mystery that a few people in the gun community were also interested in solving. Hopefully the results help you make better, more informed decisions!

Long story short:
Glock magazine springs are stainless steel, and Wolff magazine springs are carbon steel.

Short story long:
In order to achieve the best results, my friend and I agreed that we should scan both the inside and outside of the springs. This would ideally tell us if there is a coating on the springs (like molybdenum) or not. I pulled a Glock and Wolff spring from my collection, cut them in half, and sent them down to Drexel University in Philadelphia -- where we both went to school.

Upon receipt, my friend treated and cleaned each spring so no outside materials like gun oil would corrupt the data. Each spring was then subjected to testing on both the cut portion of the spring (cross section) and the external portion of the spring (surface).

For the Glock spring, the results show that it is high in chromium and iron -- i.e., stainless steel. In particular, the testing shows that the Glock springs are either 301 or 316 stainless steel, though probably 301 since it is widely used as a spring steel. This is slight conjecture, though, as neither of us possess an exhaustive knowledge of stainless steels.

For the Wolff spring, the results show that it is...iron, and really nothing else. This isn't a huge surprise, as light elements like carbon don't show up well in SEM tests, but considering this is a steel spring, we know the carbon is there and just doesn't show up in the test (same goes for the Glock spring). Therefore, the Wolff spring is some type of carbon steel, though we can't scientifically say which type with any certainty.

There are also a few other elements in there, mostly of note being silicon. Both springs, he guesses, were coated in some sort of silicone-rubberish coating, and the Wolff spring also shows some zinc, meaning it may be galvanized in some way.

Either way, the take away here isn't the coatings or other elements. The take away is that Glock magazine springs are stainless steel and the Wolff springs are carbon steel. No magic. No Keebler Elves creating mithril in the Appalachian Mountains. No incredible advances in material science. Just stainless and carbon steel.

Hope you all enjoy. :)

(NOTE: data labeled IA are related to the Glock springs, and data labeled IB are related to the Wolff springs. Micro images show what was tested -- which was a rasterization of the entire image. Macro images included to simply show where the micro images were taken: the center of the picture. PDFs included with approximate element quantities. I did not include some extraneous data, as this is the important stuff.)


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GLOCK:
http://i12.photobucket.com/albums/a202/XLordShortyX/IA01CrossSectionImage1_zps2060f67c.jpg
http://i12.photobucket.com/albums/a202/XLordShortyX/IA01CrossSectionImage2_zps5643994b.jpg
http://i12.photobucket.com/albums/a202/XLordShortyX/IA01cross-section_zpsc899f133.png


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WOLFF
http://i12.photobucket.com/albums/a202/XLordShortyX/IB01CrossSectionImage1_zpsf2ed4eab.jpg
http://i12.photobucket.com/albums/a202/XLordShortyX/IB01CrossSectionImage2_zpsa965a22c.jpg
http://i12.photobucket.com/albums/a202/XLordShortyX/IB01cross-section_zps560033f1.png

[opngrnd]

Excellent research! The questions for me would then be:
A) Is the quality of the springs based on the materials?
B) How many other magazine types would be improved if they used the same materials?
C) Is there more to it than just the materials that make these "good" springs?

[Crow Hunter]

I don't think that it is as much a factor of the materials as the designer not pushing the limit of the springs capabilities so that they material used isn't stressed to the point of failure by using inappropriate spring diameters, coil number, too many rounds in the magazine, material, etc for the work it has to do.

If I were going to hazard SWAG, based on the orginal design intent of the magazines to not drop free so the user could retain the magazine and the fact the magazine is an integral part of the ejection cycle, I figure they were not designed around the idea that magazines are a consumable. So they were "over built" so as to have a longer nominal lifespan than magazines designed around a more consumable design intent or one that isn't necessary to eject the fired cartridge case.

Wolff, being in the spring business, just reverse engineered what the spring rate and fatigue life was for the Glock designed springs and substituted a suitable secondary material that probably meets or exceeds what Glock designed in.

Or, it could be special Glock Sauce they dip them in before they assemble them.:p

[learner-gr]

Is there anyone that uses full (17 rounds) or almost full (14-16 rounds) in G17 magazines and have them over 10-15 years and find that have malfunctions?

[DreadPirateMoyer]

Excellent research! The questions for me would then be:
A) Is the quality of the springs based on the materials?
B) How many other magazine types would be improved if they used the same materials?
C) Is there more to it than just the materials that make these "good" springs?

To answer all 3 questions: the general quality of a spring depends on a vast number of variables, including material, geometric design, post-process treatment, and a ton of other factors. It's very hard to make any claims about spring quality simply from knowing their materials or extrapolating the performance of other springs if they were made of the same materials, as material is actually only a very small piece of the puzzle.

The point of this test was mostly to assess corrosion resistance, which has more to do with material than most other properties of springs. I live in a corrosion-heavy environment, so when purchasing extra-power springs for my Glocks, I needed to know what the two biggest players on the extra-power market (Glock 11-coil OEM springs / Wolff +10% Extra Power springs) were made of. Since it was impossible to find out, my friend found out for me. :)

I wouldn't make any assumptions about other performance/quality issues outside of that, mostly for 2 reasons: this test can't tell us those answers, and most importantly, both companies are already known to make quality springs. Thus, since both sets of springs are "good," my only concern left when choosing an extra power spring was how they handled corrosion. Babam!

[SmokinSigs357]

Impossible! I thought all things Glock were hand made by Merlin out of Unicorn Horns and tested by Zeus!

How disappointing...