I'm not sure that it was called the Mk2 version. What happened was that the kit came as an assembly and replacement parts were not easily available so the kits fell by the wayside through lack of use. After that, there was a suggestion (called GEMS) doing the rounds that used a spent case with the primer and pocked bored out but you still got parallax at the muzzle. The sub-cal idea camwe on stream and the barrel was an available spare part via Ord so that's what we used thereafter.

Is that about right Tankie. Feel free to correct me re the sequences. The good thing about the kit was that you could do it in any 15m(?) distance/space such as a warm classroom