Just to clarify the bucket o' worms UK weapons collectors are facing:
From Wikipedia:
Parliamentary sovereignty, parliamentary supremacy, or legislative supremacy is a concept in constitutional law that applies to some parliamentary democracies. Under parliamentary sovereignty, a legislative body has absolute sovereignty, meaning it is supreme to all other government institutions (including any executive or judicial bodies as they may exist). Furthermore, it implies that the legislative body may change or repeal any prior legislative acts. Parliamentary sovereignty contrasts with notions of judicial review, where a court may overturn legislation deemed unconstitutional. Specific instances of parliamentary sovereignty exist in the United Kingdom and New Zealand.
So basically there are no checks and balances whatsoever on Parliament's legislative powers.
And for a larger overview of gun/weapons laws in the UK and how they reached the current sorry state of affairs:
http://en.wikipedia.org/wiki/Gun_pol...United_Kingdom