Hello again, this might be a silly question, but the only stupid question is the one you don't ask right?

My daily carry is a SW1911, and there's nothing I'd prefer! I really like it, but mine spends much more time 'cocked and locked' than it does empty and 'at rest' with the hammer up. i know John M. Browning is THE genius of gun makers throughout history, but that being said, curious if anyone out there who is knowledgeable and has used their 1911 for a decade or two can tell me how long it takes for the hammer-spring to 'fatigue' or lose its oomph, or if that isn't even an issue with this great platform... Is there a recommended point to switch out the spring after a general number of rounds or years?

The mainspring is never overstressed, and will not take a set or weaken from being left cocked. It will weaken eventually with repeated cycling, say 3000 rounds or more.

From my understanding, spring fatigue is caused by cycling, not by being stored extended or compressed. In other words, it is the number of hammer falls that determine the life of the spring, not if it is stored compressed or relaxed.
The number of cycles a spring is good for is determined by the designer when he selects the material for the spring and how it is to be wound. My guess is you can't afford the ammo that it would take to wear out your spring.
My opinion, Ed

Thanks! Your input is greatly appreciated. So now I'm curious: i dry-practice often, every day that I don't go to the range I dry practice a few times, and I do use snap caps. Do you think this wears the spring out the same as live rounds do? I ask because the hammer falls just the same as if it were live-fire. This is a S&W 1911 as far as quality is concerned. I really love this gun, i can't say enough good things about it

The hammer hasn't given me any reason to worry about this, I was just thinking about how it spends most of its time 'cocked, locked and ready to rock, Doc" so I figured I'd ask.

I've already shot over 1000 rounds through it and it shoots the same if not better than when it was NIB.

I've got a 1911 produced in 1913. So far as I know, it's still using the original mainspring, and yes it was carried cocked and locked for quite a few years.

I knew quite a few dedicated IPSC competitors back in the day, I'm not aware of any of them bothering to change mainsprings. Recoil springs yes, mainsprings no.

Wow! Thanks WRMoore good to know! I do have a few recoil springs, and I use a recoil-buffer-ring as well, I know some people don't like 'em, but it hasn't messed up cycling at all, and it seems a bit comfier with it on.

Seems like I won't have to worry about the mainspring any time soon

The only time I've changed a mainspring on a 1911 is to put a lighter one in a gun I was using in competition. The standard GI mainspring is strong enough to fire the thickest, hardest GI primer ever made, and stronger than needed for US commercial primers.

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