Gene,
The barrels can be removed without taking the sliding breech off. Slide the breech fully to the rear. The main spring, the forked spring in the opened slot, should be tilted down towards the muzzle end. if you have to depress the spring, use a finger, but nothing more than a plastic ball point pen to apply pressure. With a hand around the barrels and the forend, jab the muzzle into a carpet. The barrels will slide rearward slightly and separate from the forend/stock assembly. The mainspring is semi-unobtanium so that is the reason you shouldn't use more than a finger or plastic ball point pin to depress the spring and don't press on the serrated fork; just above the serrations is where the pressure goes. I had to replace the spring on my R10 and was very, very lucky to get it done. If you break the spring, highly unlikely, you'll be screwed, very likely. Here's detailed thread by Ted on disassembly. That's a great gun. I'm opening dove season with my R10 16.
http://www.doublegunshop.com/forums/ubbthreads.php?ubb=showflat&Number=439660&page=3
