I read it to mean that they were “tightening up” on the category: ‘Single shot pistols’ and placing more of them in (or, these particular guns no longer fall outside) the ‘Dangerous Pistols’ (did I read that right?) category, which I suppose makes them Unclean in Californastan.
My bad:
‘Dangerous handgun”= ‘Unsafe handguns’
Whatever. Safe and unsafe handguns.
Heh