Hi Roger,
I have a cartridge in my collection based on a fire formed .404Jfrs, that I couldn't identify. I first thought it was a .450 Howell, but I got the drawings from Ken Howell, and it didn't match. Also looked at the .450 Vincent and others that you mention. You have now identified it. Just taken the measurements from your link. I don't know how I really came by it, think it was in a job lot auction of stuff I bought. Been thinking of building somthing with it or going for a .450 Howell, by rechambering a .458win Parker Hale or a Zastava as these come up now and again at a good price. I'm runiing a Win M70 .458 Lott that I rechambered and its working well, so I don't really need to do it but it maybe a long winter project. I would be very interested how you get along the .450 African. Looks like it will more or less the same as the Lott. Would be interested to know if you can use 450gr Barns TSX in it without compressing loads and get around the 2200fps mark.
Below left to right .450African, .458winmag, .458Lott
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