As pointed out already all springs are not created equal. If you want to test your springs take the spring out of a functional magazine and measure the length, write it down where you can find it again. And then after the mag. has been loaded for an extended period of time pull out the spring and measure it again. A slight change is usually not a problem but if it changes very much replace the spring. Not all magazines come apart but most do for cleaning. <br><br>