True or myth?

[Scarecrow]

How about a compromise: Do whatever the hell you want with your mags; if it makes you comfortable to store them empty, then do it; if you store them loaded for decades, then do it. The fact of the matter is that they will last for hundreds, if not thousands of loads and reloads and re-reloads before(if) they fail. I, personally, have only seen one mag spring failure, and that was on a 20 round m16 mag that I found in the arms room in my unit in Korea that had been hiding since probably the 50's or 60's. It failed because the spring was rusted and I was too much of a dumbass private to know to take the thing apart to check it before using it. Since then I have been part of hundreds of shoot covering millions of rounds and hundreds of mags and I have NEVER seen another spring failure.

It obviously happens, since they sell replacement springs all over the place, but that is why we pull our equipment apart and inspect it before we use it.

 

[xcom]

Don't worry Devil and Sucksky are going to settle this hash in MA and we'll only be able to load 7 in our 10 round mags. He's saving our springs!

 

[M1911]

There is no such thing as "partially compressed" and "Fully compressed". Either the metal deforms plasticly or not, and fatigue is a function of the number of times something has been flexed.

My point exactly.

 

[Gammon]

What is fully compressed? What is partially compressed? It all depends upon the design of the spring. As long as the spring isn't compressed to the point of plastic deformation, then it will return to its original shape when unloaded.

The car analogy actually is an apt one. In both cases the springs are under constant load. Constant load doesn't break springs, provided that load is within the springs design limits. What causes car springs to break or sag? Being overloaded and/or many compression/extension cycles is what wears out springs. Your car just sitting in the driveway on its springs doesn't wear them out.

Once again, I'm not risking anything by leaving mags loaded for years. Compressing and extending springs over and over by loading and unloading springs is what wears out springs.

I'll make my offer again - $50 says my mags that have been loaded for more than 10 years still work.

Fully compressed would be close to coil bind; i.e. there is no play left, the spring cannot collapse any more. This happens only infrequently in automotive springs; usually the suspension doesn't travel this far in normal use. If this were the norm, both vehicles and springs would have a shorter service life. A vehicle at rest places a certain load in its springs which are usually somewhere in the middle of their range of motion.
To simulate the stress placed on mag springs, the motor vehicle spring would have to be completely collapsed during storage, much like a loaded mag. Obviously this doesn't happen. Automotive springs are not designed to go through a complete cycle on a regular basis. Mag springs do this on a regular basis. We are talking apples and oranges.

Compressing mag springs over and over may wear them out, but I think that most shooters don't perform this function often enough to do any damage. Leaving them compressed for extended periods of time might exceed the stress that they were designed for.

The real question is why? I have heard what I assume to be expert testimony that magazine springs can survive ten or more years of full compression. I am still unwilling to bet my life on it. In this case the bet is a lot more than $50.

 

[garandman]

I've started to hear this about m1 enblock clips as well. Considering I have fired cans of clips that were loaded and in storage for 40+ years I would call this a myth as well.

Try and bend a Garand clip by hand. Not easy.

 

[dcmdon]

Fully compressed would be close to coil bind; .

And in a properly designed magazine, the spring is nowhere near its plastic deformation point when the coils bind. Which means a properly designed mag can remain fully loaded indefinitely with no problems.

 

[M1911]

Compressing mag springs over and over may wear them out, but I think that most shooters don't perform this function often enough to do any damage. Leaving them compressed for extended periods of time might exceed the stress that they were designed for.

Stress is defined as a force divided by area. By definition, the stress in the spring of a loaded magazine does not increase over time - it is constant. If the magazine spring was not overstressed during initial loading than it won't ever be overstressed just sitting there.

Steel generally has a stress strain curve that is linear up to the point of failure. Provided the steel is not loaded to the point of plastic deformation, once the steel is unloaded it returns to its original shape. In other words, if you load steel below its yield point, it doesn't lose strength over time.

The real question is why? I have heard what I assume to be expert testimony that magazine springs can survive ten or more years of full compression. I am still unwilling to bet my life on it. In this case the bet is a lot more than $50.

I've told you why. You are causing more wear on your magazine body and spring by repeatedly loading and unloading it than by just leaving it loaded. You are not decreasing your risk of magazine failure - you are increasing (ever so slightly) your risk of magazine failure.

 

[Pilgrim]

I've got mags that have been loaded for over 60 years.....guess what.....they're perfect.

Gammon, it's an accepted fact that magazine springs are not damaged by being left compressed, and that the frequent loading/unloading is what causes problems.

If it doesn't make sense to you, it's because you don't understand the metalurgy, and just because you don't understand it, doesn't make it wrong.

Believe it or not. It's up to you.