There's absolutely no legal issues at all Clarkie. Cleverly inserted into the act somewhere in the not too distant past was a clause that said, basically and to the point, that the Secretary of State can (no need for any discussion with that statement.....) ban any type of weapon that he considers dangerous or likely contravenes this that and the other. There it is. You pays your (big) money and takes your chance. The niceties of legal definitions and learned opinions don't count.