Now can we tackle the magazine spring myth?
It's no myth.
Whether it is true or not is entirely dependent on the
quality of the spring in question.
it was a general truth at one time, springs left compressed could "take a set" and weaken or even completely lose their spring properties.
significant advances in spring tech began around the turn of the century, and are still going on.
There are numerous examples of magazines being found fully loaded for long periods of time, and working flawlessly when used. Some from WWII.
Modern metallurgy says a quality spring is not affected by being compressed for a period of time. OVERcompression does cause damage. Normal wear happens during the compression/relaxation cycle, not at either end.
Unfortunately, the only way to tell if you spring actually IS the quality it is intended to be is to see how it behaves over time.
So, essentially, IF your spring weakens from being left loaded, its because it wasn't a high quality spring to begin with, despite (or because of) the makers wishes.
After my Dad passed, I found his Colt Govt Model, in his dresser drawer. Mag fully loaded. The gun had been there some time, I estimate 10 years, maybe more, the oil had turned to gum thick enough that the slide slooowly closed and stopped about half way shut.
After all the old gunk was cleaned off and the gun re lubed, the original loaded mag was fired 7x7 flawless. I'd count that as a good spring.