I have never heard of anyone doing this, but I don't think it would be adviseable. If you want a beltless casing then buy a caliber that has no belt, there are several magnum's out there that are beltless.
Alex, I have a 6.5-300 Win Mag (beltless) that I made up a collar to have the belts cut off regular 300 Win Mag cases, but the reamer doesn't have the belt on it either. This experiement was a lot of work that turned out to not be a benefit at all when looking at the whole system. Do I beleive non-belted is better.... yes, but is using this method to solve this "problem" a good way... not in my opinion. But remember my chamber doesn't have the belt cut into it. So if you talking about cutting the belts off from an existing cases then firing them in a belted chamber the case heads will expand and you will prematurely loose primer pockets. And the worse case scenerio would be a ruptured case and leaking gas coming back in your face. Even if you jsut relief cut the front of the belt by .010" so the headspace is 100% on the shoulder eventually the case walls will swell and you will end up with a double shouldered belt anyway. There's a fella that has advertised on this board down under the "for sale and swap" section that makes a collet type sizing die to help with expanded bodies on belted cases. I don't have any belted competition rifles right now so I've never used this new die so I can't tell you how it works and the results of using it. Just an FYI to you.
How do you clean your cases and if your cases get wet, how do you dry them because I tried to air dry them and they are all tarnished and the primer pockets have some green crap in them? I hope I didn't just ruin 40 cases. I tried putting them in the microwave but I stopped when I heard crackling and saw blue flashes coming from where the primers were. Thanks
Alex, when I choose to wash my cases I do so with very hot soapy water, rinse with hot water and then invert them mouth down for draining. To ensure complete drying, i use the wifes hair blower to warm the cases to the point if you pick em up, their hot to the touch. This aids in rapid evaporation/drying. Been doing this for years with out tarnishing.
As a general rule, do not place metallic items in your microwave..