You need a name that sounds good, rolls off the tongue well, and is catchy. No mamby-pamby stuff.

For the 366:

365 Long Tom
367 Rocket
367 Gonzo

For 9.3, stick with the metrics, if you start that way.

9.3mm x 64mm Gonzo Power

Or a retro name:

368-100-286

or perhaps add a name that rolls off the tongue well with that last one.

When I did mine, I called it a 350 African Express, which is a 358 on a 8x68mm case blown out and stretched.

RobertD

Given the parent cartridge is named after its bore size, I believe your 9.3 should be as well.



I, then, propose the "358/300 Mag."



Or perhaps the old Britsh naming convention could be used instead: "458/358 Mag;" that has a nice ring to it.



Either ought to confuse the next owner of your gun.

What about the 9,3x66 Sako. It's a factory cartridge

9.3X66 is what it IS, but call it what you want

IMHO, a .358X2.62 deserves a look too, as the 35 cal bullets out there are rather short for their weight and are well suited to the long case/short chamber you are dealing with.

366 WinMag or 9.3mm WinMag-- gives us both the diameter and the parent case.

Might not be appropriate, but I like the way the 375-06 cases got named "Whelen," even I believe he had nothing to do with it. And the 375-338, did Chatfiled-Taylor actually make that, or was it just a neckd down 416 T?
I'd call it the 366 Taylor I think. (Has nothing to do with the facthat that's my name!)
In fact, when will we get a 458 Taylor? Seems that case could do with a little blowing out.

9.3 Freakin' Gonzo

Not much to work with buddy, best I could do on short notice.

How about the 9.3mm Gonzo Freak-Streak?

I think the 366/338 is the best case design, mostly because it has more neck for the heavy bullets like a 300 gr. Woodleigh...I have thought about that wildcat quite a bit, but then the 9.3x64 is about the most ideal round I can think off on this planet, it just does it all in a neat package that will work through any standard action...and now brass is available from Huntingtons, that was its only drawback....

Why not just dig out the old 9.3x70 mag and chamber that
i think ?? someone did up a few some years back's

Or the 9.3mm Gonzo Gorilla Grinder?