Yes, you can do it, not unsafe, the difference is only the length, also 9,3 x 57R/360long, 9,3 x 65R Collath, 9,3 x 70R, 9,3 x 80T Collath possible. The only problem is when you do it very often the chamber will be burn out.

http://www.municion.org/9_3/Nimrod.htm