Just a thought to consider or not - how about 9.3x74R? The rifles are "ready rolled" and available off the shelf. A friend has a Verney Carron 9.3x74R over/under - it's light and handles really well, for a super fast second shot. Price was quite good, about $4k AUD IIRC. Regulation was good - can start becoming a problem if you start looking at lower cost off the shelf alternatives.
I did see someone using a converted double barrel shotgun (SxS) at one of our events a few years ago. Don't know what cartridge it fired. I'll have to look for the photo I've got of it and post it (give me a day or two).
Last edited by mauserand9mm; 12/04/20.
