ATM the shotgun on SVN (and the whole weapon balance actually /imo/) is a work-in-progress.
If you want to help us to find better values, especially for the shotgun, check this :
http://pastebin.com/M9Vq1APd
If you want to help us to find better values, especially for the shotgun, check this :
http://pastebin.com/M9Vq1APd