Recoil spring

I am new to 1911's.  I have a Kimber Custom II Target.  I am shooting light loads (4.0 Bullseye with 185 & 200 gr. cast bullets).  I believe that the Kimber has a 16 lb. recoil spring.  The pistol cycles fine with this spring.  Should I use lighter springs for the reduced loads to extend the life of the pistol?  Thank you for your help.
Tom

If it cycles okay with that spring, leave it alone.  Using a lighter spring than necessary would shorten the pistol's life, not extend it.

Under sprung guns (I've been told and can't verify so I'm sure the smith's will be around soon to tell you the truth) will allow the gun to beat it's self to death. Over sprung guns will cause function issues. I put the heaviest spring in the gun that the gun could still function properly.

Over sprung guns will dip the front sight when the slide goes in to battery.  This just adds to the recovery time in sustained fire.  There is a sweet spot.  

Under sprung guns have chambering issues as they sometimes will not return to battery fully.  

There are other techniques to absorb the energy of the recoiling mass Or not create it in the first place.  If you use spring force to absorb this energy you will end up with an over sprung gun.

It takes more then springs. I believe it was covered in another post... but a propertly fitted barrel will serve you better then just playing with springs.