I'm afraid your argument is lost on us.
If you are asserting that I am not correct, by all means please tell the mechanism of failure for steel under static loading. If you are saying that you do not understand what I said, I will try to provide an explanation below, but I am not going to rewrite a textbook here. Use google to read up on this subject (not leaving mags loaded, but fatigue, stress, strain, creep, etc.). There is plenty of info out there from university websites, to wikipedia. You can pick up the basics anyways.
Beretta would disagree with you, ruger, etc. Frankly I would not purchase a weapon form a company that recommends against having magazines loaded and the weapon ready. What good is a weapon that can not be kept ready?
Carlton Nether, Customer Service for Beretta USA, tells us keeping a pistol magazine loaded for an extended period doesn't cause magazine spring failure, however, failures to feed can result. He says, "The ammo will 'roll' in the magazine. If the mags are kept loaded and moved around a lot -- say on a cop's belt -- the rolling action can, over time, cause creases in the cases. These creases can cause malfunctions. Also the top bullet will roll against the magazine lips and creasing can occur there as well. Just check old ammo that's been bouncing around in a magazine for a long time.
http://findarticles.com/p/articles/mi_m0BTT/is_163_27/ai_99130369/?tag=content;col1
If you understand the loading and unloading behavior of steel you would see why the notion that static loading of a magazine spring causing fatigue is ridiculous. When steel is loaded below the elastic limit, it will recover to its original length when the load is removed. When it is loaded above the elastic limit, plastic deformation occurs. This means that when the load is removed, the material will have some permanent deformation. However, the material stress strain curve will now be permanently altered and will not permanently deform any further if the loading remains the same or less. This is basic mechanics of materials. Try doing some reading on it as well as fatigue behavior of metals. You will see why I am correct and your intuition (and companies like Ruger) are wrong.
But, since you and ruger know so much more than me, please explain how the steel fatigues under static loading. Google static fatigue and you will see that this phenomenon does not occur in metals.
From Ruger FAQ:
"Can I store my Ruger pistol cocked or with rounds in the magazines?" Ans.
It is seldom advisable to keep a constant load on any compression spring and it is unsafe to store any firearm cocked."
Thank god I don't own a Ruger. How are you supposed to use one of their weapons for defense? No loaded mags, no cocked action? That leaves you with a metal club without a good handle for swinging.
From Wolff Gunspring FAQ:
." How often should I change magazine spring? Should I unload my magazines, rotate magazines, load with fewer than the maximum rounds? Ans.
Magazine springs in semi-auto pistols are one of the most critical springs and are the subject of much debate and concern. Magazines which are kept fully loaded for long periods of time, such as in law enforcement and personal/home defense applications, will generally be subject to more fatigue than the weekend shooter's magazine springs in which the magazines are loaded up only when shooting. "
Read the rest of their answer and you will see they are trying to sell you their extra strength springs.
In applications where the magazine must be kept loaded at all times, a high quality magazine spring such as Wolff extra power magazine springs, will provide maximum life. Regular replacement of magazine springs will provide the best defense against failure from weak magazine springs. Regular shooting of the pistol is the best way to be sure the springs are still functioning reliably.
Maybe they have just a little interest in selling you one of their products?
