As I am sure most of you know, back in the late 90s the UK banned all centerfire and rimfire pistol ownership  (defined as any firearms under 24″ of length or with a barrel under 12″, excluding muzzle loaders). What I was not aware of is that they allowed muzzleloading pistols to be owned by members of target shooting clubs. A company called Westlake Engineering imports .38 Special centerfire revolvers  from Armscor, without cylinders and some other internal parts, and then converts them locally into muzzle loading pistols for target shooting. The converted pistols fire .357″ diameter 148gr Wadcutter bullets, using Herco smokeless nitro powder and ignited by 209  shotgun primers.

They sell two models, a straight converson for £495 (title image) and a upgraded match pistol with upgraded barrel, targets sights and weaver rail for £850 (above).

Many thanks to Alexander for the tip.