I left my sniper cocked for a while in Sniper Rifles Posted July 11, 2011 · Report reply Constant load also wears down springs. Compressing a spring all the way for a long time adds tension on the metal and can, given enough time, alter the length of the spring by repositioning the molecules. 2 days, probably doesn't hurt it. 2 months...that might, and you'll have to re-stretch it. Just look at car springs. I hate when people say long time compression doesn't hurt springs...it does, but it depends on the spring. After 150k miles or so, compare the spring to a new OEM spring. Usually they are about .5 inch shorter and are softer. Airsoft springs are much softer than car springs, and lose their firmness faster. If it seemed fine, your spring probably isn't too bad.