My mate used to put .72 cal on his permit for his HandR rifled single shot :D He asked the DOC office where he got the permit and even showed them the HandR. They didn't seem to have a problem, they just told him don't take shot with you. I have no idea if this has changed but in thoes days it was he local offices that issued permits. Try asking them?
Personally I preferred my SKS but in the thick Ruahines bush it probably didn't matter. Most shots were 50m or less.
