Oboy, are you opening up a can of worms here. If you do a search on this topic, you see that this has been covered numerous times in the past with many conflicting views and some very interesting opinions on this subject. This is what I do and what I recommend (
from past experience, others will disagree with me, so flame away):
<UL TYPE=SQUARE><LI>Do not load your magazines to full capacity -- depending on the number of bullets that it holds, leave one or two rounds out to reduce tension on the spring. My S&W3913 has a 7-round magazine, I have it loaded with only six. My S&W5906 has a 15 round magazine, I have it loaded with only 13.
<LI> Ideally, you should have three sets of magazines: One set loaded, one set resting and one set as a virgin set -- meaning once you've verified that the magazines feed correctly, you leave them untouched.
<LI> For an everyday carry gun, I would recommend six mags: (1) two loaded; (2) two resting; (3) two virgin. For a home defense gun, I would recommend nine magazines: (1) three loaded; (2) three resting; (3) three virgin.
<LI> Every season (meaning winter, spring, summer & fall), or every three months, take the bullets out of the loaded magazines and place them in the resting magazines.</UL>
Some will flame me and laugh at them suggesting telling personal stories of how they kepts a 1911 loaded for years and how the magazine worked flawlessly. Well, I have those stories too: I had a S&W659 loaded for about half a dozen years and then magazine fed without a problem but I also have stories on the other side as well ...
After a range session, I cleaned my Para-Ordnance P14-45 and loaded the ten round magazine with all ten bullets. For various reasons, I didn't get a chance to shoot this gun until almost a year later. The first few rounds fed will and then the rest just failed to feed because the spring was under so much tension that it just gave out. Fortunately, this happened at the range and not in real life. This event has re-enforced me to follow the precautions that I've outlined above.
Share what you know, learn what you don't -- FUD