Even IF having a round in the chamber did eventually weaken the spring (I assume you mean -firing pin spring - (same would hold for any spring). The springs for the P-3AT are cheap -
(firing pin spring is $.80) so - if you are concerned - you could just replace it every 2 years.
But what is the alternative?
Carry around a gun that is not ready to be used.
Maybe the BG will listen when you ask him to - PLEASE wait 10 seconds before you stab me so I can load a round in the chamber and shoot you!
I agree with the above posts. z71bill put it best...
"...carry(ing) around a gun that is not ready to be used."
If it's not loaded with one in the pipe and full magazine, there's no point in having it on your person. By the way, you need good holster to prevent accidental discharge. I.e. something that covers the trigger completely.
If the time ever comes and you have to draw your weapon, you want it to be ready...without a doubt. Under stress, you don't want to think about ANYTHING other than stopping a threat if you cannot remove yourself or a loved-one from the situation. Oh, and don't forget, what's BEHIND your target if you pull the trigger and miss???
Operating the slide to load the gun doesn't cock the hammer. (well, it does, but it doesn't stay cocked)
Pulling the trigger cocks the hammer.
It is never left resting in the full cock position.
When the slide goes forward, the hammer follows it down to rest on the hammer-block safety. There is very little tension on the hammer spring in this position.
It is always at rest on the hammer-block safety unless you pull the trigger to cock and release it.
Leaving the gun loaded indefinitely will have no effect at all on the hammer spring.
There is no effect on the firing pin spring whatsoever.
It is always spring loaded to the rear, until the hammer hits it and drives it forward, then it immediately springs back to the rear position as the slide cycles.
Loaded or unloaded makes no difference at all to the FP spring.
I think a similar dicsussion about springs came up on the PF-9 board...and I do believe this topic is about springs, and not anything else.
Wound springs have a lifespan based on how many times they are designed to stretch and relax - not how long it is held in either of position. Obviously, the quality of the spring's material is important too.
If I'm incorrect, please chime in. (I know somebody will disagree, regardless.) 8)
I read somewhere, perhaps in a NRA publication, about magazine springs losing their tension when compressed for a very long time. I think the conclusion was don't worry about it. But if you're that anal, change to a second magazine every 6 months and unload the first one.
If a fully loaded magazine does causes a spring to become weak (over time) / or if it just becomes weak because of use - would it still work for the first several shots - and then fail to load the last 1 or 2 rounds? So you would still have 5 shots / maybe 6 before the problem would show up. Not good to have any type of failure - but not near as bad as thinking you have 7 shots - and ending up with a single shot "semi auto".
Every time I go to the range (about once every 5-6 weeks) the first thing I do is shoot the magazine that I have been carrying. Since I have never had a failure (with any gun) shooting my carry magazine it gives me a little bit of confidence.