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reynolds357 12-19-2011 09:36 PM

Wildcat question
 
I have never seen either of these wildcats, nor do I have any information on either of them in any of my cartridge books; but I am sure one of them has to exist. For some reason, I have an insatiable desire to make .264 bullets go ultra fast. I have always said I am through with wildcatting and am not going through the hassle of developing any more of them. Having said that, I want a wildcat .264. Is there a .264 Wildcat in existence that has a full length 8mm Rem Mag or a full length 300WBY mag as the parent case? If so, what is it called, who makes reamers, and does anyone have any loading data?
Thanks in advance for any help.

Just as a note, I am well aware it will be a 500 shot or less barrel life wildcat.

Bindernut 12-19-2011 11:14 PM

I have read about at least three different versions of a 6.5STW but have never seen one in person. It's the 7mmSTW (the 8mmRemMag necked down to 7mm) necked down for .264 bullets.
Google turned up this page of one guy's version with a bit of load data. No info on reamers though.
http://www.accuratereloading.com/65mmstw.html
Personally, I'd pick a different twist rate than what was used so it would work with heavier bullets too...but if you want a .264 1000-yd prairie dog rifle it sounds like the hot ticket.
In fact, I have seen a .257STW...about the same as necking it down to .264, it would also be a limited life barrel.

Another parent case that would be a similar or even larger capacity would be the .300 Remington Ultra Mag. There is a version called the .264 Ultracat.
The 7mm and .300 RUMs are a ridiculously inefficient pair based on the .404 Jeffery case. It would be mildly worse squeezed down to .264 or .257...but if it's already that far overbore in 7mm then what's another couple percentage points less efficiency right? :)

Do you have a copy of Ken Howell's "Designing and Forming Custom Cartridges for Rifles and Handguns"? You could get lost in that book for a long time. He does a good job of explaining the science of and his personal theories on wildcatting.
Like Gibbs, O'neil, Ackley, Neider and all the other "old-timers", Howell puts the ideas down on paper pretty well and is must-have reading material.

reynolds357 12-19-2011 11:46 PM

Re: Wildcat question
 
Quote:

Originally Posted by Bindernut (Post 840973)
I have read about at least three different versions of a 6.5STW but have never seen one in person. It's the 7mmSTW (the 8mmRemMag necked down to 7mm) necked down for .264 bullets.
Google turned up this page of one guy's version with a bit of load data. No info on reamers though.
http://www.accuratereloading.com/65mmstw.html
Personally, I'd pick a different twist rate than what was used so it would work with heavier bullets too...but if you want a .264 1000-yd prairie dog rifle it sounds like the hot ticket.
In fact, I have seen a .257STW...about the same as necking it down to .264, it would also be a limited life barrel.

Another parent case that would be a similar or even larger capacity would be the .300 Remington Ultra Mag. There is a version called the .264 Ultracat.
The 7mm and .300 RUMs are a ridiculously inefficient pair based on the .404 Jeffery case. It would be mildly worse squeezed down to .264 or .257...but if it's already that far overbore in 7mm then what's another couple percentage points less efficiency right? :)

Do you have a copy of Ken Howell's "Designing and Forming Custom Cartridges for Rifles and Handguns"? You could get lost in that book for a long time. He does a good job of explaining the science of and his personal theories on wildcatting.
Like Gibbs, O'neil, Ackley, Neider and all the other "old-timers", Howell puts the ideas down on paper pretty well and is must-have reading material.

Thanks for the info. I will try to find a copy of the book. The .264 Stw sounds appealing. I guess I will dig into it further.

H-D 12-19-2011 11:49 PM

Re: Wildcat question
 
I'd settle for a 6.5-06 Ackley Improved , but I'm a sucker for the -06's :)

reynolds357 12-20-2011 01:34 AM

Re: Wildcat question
 
Quote:

Originally Posted by H-D (Post 840979)
I'd settle for a 6.5-06 Ackley Improved , but I'm a sucker for the -06's :)

I would probably go with the Hawk before the Ackley, but both are a slight step down from the Win mag which I already have three of. One is borderline needing a new barrel and after its rebarrel, it is no longer going to be a win mag.

jack404 12-20-2011 01:55 AM

Re: Wildcat question
 
1 Attachment(s)
300 magnum based suit you ??

jack404 12-20-2011 01:56 AM

Re: Wildcat question
 
Nice round eh , you can throw a very long (heavy) projectile a long way in a rather straight line ...

JLA 12-20-2011 07:40 AM

Re: Wildcat question
 
Beat me to it jack. That would be my choice As it wouldnt require anything special from an action standpoint. a std .300 winmag action and a barrel short chambered for the 264 winmag. Either route you go would be a throat burner though. just make sure you go long on the barrel length to burn those monster loads of slow powder.

I find 26" about right for short action overbores like the .243 win to completely suck up a 40 grain charge of IMR4350, so with something like the .264 winmag thats gonna hold around 60 grains of the same powder, id go with at least a 30" barrel, but thats just me.

jack404 12-20-2011 07:46 AM

Re: Wildcat question
 
a Win 70 would a a great start for a platform for it to , not so expensive a start

CHW2021 12-20-2011 09:05 AM

Re: Wildcat question
 
You guys are quite out of my league, I have a question re. throat burning. With the current wide variety of powders available and different burn rates ect.... Can the throat erosion be minimized compared to "back in the day" or is the problem basically the same?

Humor me.

jack404 12-20-2011 09:27 AM

Re: Wildcat question
 
hypervelocity is a barrel burner at all cal's fact! ( sorry ) its a balance

Chrome bores !!!! lots more life with punch ;)

Freebore 12-20-2011 10:19 AM

Re: Wildcat question
 
Take a 375 H&H shorten up and blown out, then necked down to .350.....then again neck that down to .264 and you have a 6.5 Remington Magnum.....a great cartridge in short actions.

reynolds357 12-20-2011 10:23 AM

Re: Wildcat question
 
Quote:

Originally Posted by jack404 (Post 841002)
300 magnum based suit you ??

That is what I am already shooting. Have three of them. I need to re-barrel one of them and I want to step it up a few hundred FPS when I do.

JLA 12-20-2011 10:29 AM

Re: Wildcat question
 
Quote:

Originally Posted by CHW2021 (Post 841096)
You guys are quite out of my league, I have a question re. throat burning. With the current wide variety of powders available and different burn rates ect.... Can the throat erosion be minimized compared to "back in the day" or is the problem basically the same?

Humor me.

For the most part Jack is right, overbore cartridges are just barrel burners, but with todays ever evolving powders and bullets you can to an extent prolong throat erosion by being selective with your powder. Usually in an overbore cartridge like the .243 they will be loaded with slower than youd think powders anyway, but it is possible, and I have seen it done to use an even slower powder to get a cooler burn, but the trade off is lack of efficiency and velocity loss. The best way to minimize throat eronsion IMO, is to shoot the heaviest bullets that your barrel will stabilize and use the slowest powder listed that gives a complete burn.

reynolds357 12-20-2011 10:36 AM

Re: Wildcat question
 
Quote:

Originally Posted by JLA (Post 841127)
For the most part Jack is right, overbore cartridges are just barrel burners, but with todays ever evolving powders and bullets you can to an extent prolong throat erosion by being selective with your powder. Usually in an overbore cartridge like the .243 they will be loaded with slower than youd think powders anyway, but it is possible, and I have seen it done to use an even slower powder to get a cooler burn, but the trade off is lack of efficiency and velocity loss. The best way to minimize throat eronsion IMO, is to shoot the heaviest bullets that your barrel will stabilize and use the slowest powder listed that gives a complete burn.

I used to take care of my barrels and try to baby them. I found that it makes less than 100 shot difference. The .264 I am about to re-barrel has conservatively estimating 600 shots on the barrel. Probably closer to 800. That is really not that bad for a hunting rifle that has lived its entire life shooting loads way over maximum. 95% or those shots were me playing around at the range. It still does not have to be re-barreled. It is about a 3/4" at 100 shooter, but it used to be 3/8" and is opening up pretty regularly. I could sell it and 99% of the people would not see anything wrong in the bore. They would even be thrilled with how it groups.

jack404 12-20-2011 10:40 AM

Re: Wildcat question
 
If your ok with that ( i have .416 Che Tac 400-500 barrel life ) go for it as long as your aware ;) all's good :D

reynolds357 12-20-2011 12:13 PM

Re: Wildcat question
 
Quote:

Originally Posted by jack404 (Post 841130)
If your ok with that ( i have .416 Che Tac 400-500 barrel life ) go for it as long as your aware ;) all's good :D

For the most part, I punch paper with bench rest rifles. I do play with my .264's a bit, but most of the rest of my stuff is hunting only. About the only thing we have to hunt around here is deer, hogs, and Coyotees. You can not shoot many deer in a year. Hogs get shot at close range. Coyotees are so few and far between on a good year I kill 5 or six of them. Unless I go to the range and just shoot to be shooting, I am not going to burn a barrel up in my lifetime on a hunting rifle. If I built this rifle, it would not punch paper.
A hyper velocity .416 is on my list of rifles to aquire, but I am not sure if it will be the Chetac or not. It will probably be the Barrett.


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