Real CGN-wildcat-thread-soon-to-be-forum

I was doing some thinking, and had a question to ask the wildcatting gurus. How much shoulder does a cartridge need to headspace properly? Futhermore, a cartridge without a belt? I would assume headspacing on the belt of a belted magnum is completely acceptable (although maybe not desireable) and there we have a belt diameter of .532" and a body diameter of .513" for a "lip" of only .019". I understand this is a 90 degree angle to the case, but what about a lip of 35 or 40 degrees (again, on a non-belted case)? I see Z-Hat is necking up the 30-06 case to .375 and .411, the latter giving very little shoulder. I would also assume the quality of the chamber would be a factor.
Thanks.
 
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1899 said:
I was doing some thinking, and had a question to ask the wildcatting gurus. How much shoulder does a cartridge need to headspace properly? Futhermore, a cartridge without a belt? I would assume headspacing on the belt of a belted magnum is completely acceptable (although maybe not desireable) and there we have a belt diameter of .532" and a body diameter of .513" for a "lip" of only .019". I understand this is a 90 degree angle to the case, but what about a lip of 35 or 40 degrees (again, on a non-belted case)? I see Z-Hat is necking up the 30-06 case to .375 and .411, the latter giving very little shoulder. I would also assume the quality of the chamber would be a factor.
Thanks.
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A very good question to which I don't think there is a definitive answer. The "lip" on a belted magnum is in fact half of what you quoted, but like rimless handgun cartridges which headspace on the lip of the neck, the angle is 90 degrees as you pointed out and found to be more than sufficient. It is a consistent reference point that's needed, not a strong force bearing surface - you need "just enough" force to keep the cartridge firmly against the boltface when the firing pin drops.

Of course once the angle changes to 40, 35, 30, or less, the backwards force is diminished, and even "fireformed" cartridges have some slack (the brass bounces back to a smaller size than the chamber after firing).

"They" say that the 411 Hawk is the limit, and that is what I'd use as guidance. If the shoulder angle was to be less than the Hawk's (40 degrees?), I'd make sure I had more shoulder, if more, I'd stay where I was.
 
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I think it's time to update my list
17 Ackley Bee
22-303 Brat Improved
223 Ackley Improved
6mm-303 Brit Improved
6.5mm-300 Win Mag
303 Brit Improved
458 Canadian basicaly a 458x2" actual 458x2 1/16 or a 450 marlin on a small belt
458-350 Rem Mag 350 Remington blown straight and necked back down to 458

The other definition of a wild cat are ones that are no longer in production .
25 Remington
30 Remington
303 Savage? Ok Joe now it's only endangered
32 Remington
8x60S Mauser

Rich
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The only wildcat I have been using this summer is the 223 Ackley Improved.
26.5gr WC845 with 55gr Barnaul HP.Win cases weighing 96-96.9 gr and the bullets weigh 55-55.6 gr. Hell on gophers.:evil:

Rich

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RR said:
I think it's time to update my list
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6.5mm-300 Win Mag - in at the smith as we speak.
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458 Canadian - had one until I ran a 458 Win Mag reamer into it, now it's a "458 WM "Improved" as it now has a neck. :)

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Rich​
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Any loads for the 6.5mm/300 WM you can share with me?
 
Andy
All my load notes for that thing got water damaged:rolleyes: .So I am starting over.
Start with 264 win mag loads and work up.I have a box of ammo waiting to try.As it's 7828 I am waiting for somewhat lower temps. 139 Scenars from 65 to 68 gr 7828 CCI 250 primer 3.520 OAL.
Rem 140 PPCL 65 to 68 7828 3.46OAL.

Rich
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Rich,

My thinking exactly - 264 WM max loads and working up. There is some sense to using 7mm RM loads, as the greater pressure caused by the smaller bore in the 6.5 is off-set by its larger case.

I'm thinking full or near full cases of RL25, H1000 or US869 over 140's will rock.
 
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