Altering length of hull

[Drew_CarreyAB]

I was wondering if a person could alter the length of the hull to make 2 3/4" shells. IE 3" or 3 1/2" cut down to 2 3/4" length. Reason is, is that I've found lots of 3" and 3 1/2" high brass, but no 2 3/4" hulls to use and would rather build slug loads out of 2 3/4" than longer. Is it possible? Or better yet, safe to do?