.300 Durham Magnum

[old03]

has anyone heard of a 300 durham magnum?  I've found a custon 1917 enfield with a douglas barrell in 300 durham magnum and am having a hard time finding info on the caliber.

Any info would be appriciated.

[Catfish]

The .300 Duemham Mag. brass can be formed from the .300 H&H mag. brass. Full lenth size in the Durham size die with the expander plug removed and trim to lenth. Fire form in the the Durham chamber. If you need more info. PM. me.

[old03]

pm sent,     I picked up the gun at a great price but know nothing of what the cailiber is capable of.

[Wyo. Coyote Hunter]

  When you get this one running let us know how it performs. It seems to me I have read about this, but who knows. Age is catching up with me. Anyway, these old wildcats are interesting. Most have nothing on  our current crop, but they sure look back at a time when we were limited to a hornet, swift, 257, 270 30-06, and .35. Rem. Some might like those days but for a gun man it was pretty boring unless one had the $$$$ to fool with wildcats.   

[Catfish]

old 03, I just got to thinking( I know trouble), but the old .300 H&H was not a 60,000 psi round, at least as I rember, But I would still use loads down 10% from .300 H&H to start and watch for presure, but if no signs on the hotest tepms. you will ever shoot it in you should be able to go on up above what the book says for the H&H, but watch for presure signs and if your not sure back off.

[old03]

OK....might now I'm not 100% sure I'm dealing with a 300 durham
that cartridge has a 45 deg shoulder, I measured my fireformed brass at 30 degrees.

here are the case dimensions:
Case type: belted magnum
Case length: 2.55"
Head diameter: .513
rim diameter: .532
shoulder diameter: .482
length to shoulder: 2.085
Shoulder angle: 30 deg (was a 300 durham up till this measurment now)



anyone know of any online diagrams of wildcat rounds?

[old03]

I found another round that matches the case a llittle better,  300 APX (not apex)

I think working up a load won't be too hard, I'm planning to start at the bottom of the 300 win mag (about the same case capacity)

The only other question I have is how to get dies for the thing,  anyone know a source of reasonable priced custom dies?   I could rechamber the thing for a couple of hundred, but would much rather keep it as is.

[swifty22]

old03, It is almost , but not, a 308 Norma, the only difference the drawing shows for the Norma is a 25 degree 30' shoulder angle and a shoulder dia of .489, I would think that 308 Norma book starting loads would be appropriate. You might even be able to use the Norma dies if you could find a used sizer to try. You could at least use the 300 Win for shoulder dia and maybe part of the neck. _Muddy

[41 magnum]

The Durham Magnum line of cartridges load data is in P.O. Ackleys--Handbook for Shooters and Reloaders-Vol 2

They are all based on a reworked 300 H&H case