the thing about deactivated guns being easy to re-activate is bollocks. Even "old spec" guns were such that to re-activate them properly you would need the technical knowledge and tools such that you could manufacture a gun anyway.

New spec guns were designed to be even harder to convert because it was found that the availability of old spec deacts was such that they were cheap enough to make converting them viable. hence the new spec guns which are just paper wieghts that look like guns!!!

The brocock air cartridge revolvers were banned because they were just too well made so could handle the pressures of a small handgun cartridge going off. The BACS even looked like a shell casing and worked in a similar way with firing pin etc. there was even a mini version used in a walther PPK replica that worked just like the original and with a few mods and an upping of the pressure could be made to self reload Also again too well made so easily rechambered for handgun calibre rounds.

Shame really, i had designed a nice AR15 style rifle using BACS. would have been ace!