Thanks for you work on those pictures. I would be OK on using an Enfield action, if I could find one, and I have to confess that I haven't even tried. One concern I had was that I know that they reworked them pretty completely, and maybe that is less than it sounds. Maybe it isn't a lot more than fabricating the metal box; installing an aftermarket trigger; working out the feeding problems; and of course generally squaring up the action.CZ 550 Magnum is not a standard length action opened up. I have 4 of them. One is a 450 Rigby, one is a 416 Rigby. Other two are awaiting barrels.
CZ550 would be my choice.
I will take a photo later, I have some 510 Cartridges. I will place one on the follower to give you an idea.
My gunsmith says he likes to work with the Demoulin action but it does need work. One issue I encountered was the hardness of the steel used. It turns out the Brno 602 has been hardened in a way that can make it more challenging to work with. And, engraving is also a challenge. I don't quite understand it but that is some feedback I got. I am a huge fan of the Brno actions and you can pick up old rifles for reasonable rates.If one was making up a 9.3x62, would one not use the regular Zastava action?
Anyone have an opinion on which is better the Demoulin or the Zastava. I would probably go over them pretty thoroughly so issues that one can machine out could be dealt with. Basic differences in materials, or set-up aren't going to get touched. I like the Demoulin safety for instance (as pictured).