Reforming cartridge brass

scairns said:
I just do 30-30 up to 375 Win, a touch short but works fine in my model 94....and I got to make a home-made expander ball to do it, even more messing around for the same project!

Scott
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Scott I am sure you are aware but for the newbies out there, the 375 win operates at higher pressures than the 30-30, reformed 30-30 cases may not be up for the task, feel free to correct me if I'm wrong guys.

Noel

I forgot to mention, 30-30 to 25-35 too.:redface:
 
Noel said:
Scott I am sure you are aware but for the newbies out there, the 375 win operates at higher pressures than the 30-30, reformed 30-30 cases may not be up for the task, feel free to correct me if I'm wrong guys.

Noel

I forgot to mention, 30-30 to 25-35 too.:redface:
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Generally, the case itself does not have to withstand the pressure; it's there to function as a gasket, not a structural member. The pressure is withstood by the action in most cases. For handguns especially, the case head may not be fully supported, and will have to withstand some pressure. For the most part, this is not the case in rifles.
 
prosper said:
Generally, the case itself does not have to withstand the pressure; it's there to function as a gasket, not a structural member. The pressure is withstood by the action in most cases. For handguns especially, the case head may not be fully supported, and will have to withstand some pressure. For the most part, this is not the case in rifles.
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Don't want to sound like a challenger, but this is not true! The brass case is the weak link in the complete formula. When the case fails, the action then takes the brunt of the escaping gases. The case must hold the pressure and be supported by the action, but weaker cases always spell trouble with higher pressure loads. A typical situation is some older 45-70 cases with balloon head construction. They must never be used in a load designed for a strong action, like the Ruger #1, since the case will fail. [not the action]. Regards, Eagleye.
 
"Trying to use the weaker brass to lighten the load on the action and bolt face of a rifle by having the brass grip the chamber is analogous to using a car's radiator to protect the bumper in a front-end collision. A polished chamber minimizes case stretching, reduces case head separation, and increases case life."

from the "Finite Element Analysis of Rifle Chamber Surface Finish and how the resulting friction effects brass cartridge case stretching and bolt face loading." page at http://www.varmintal.com/a243z.htm



Basically, it's stating that the brass itself contributes negligable additional resiliency
 
Basically, it's stating that the brass itself contributes negligable additional resiliency
Agreed, it just holds the powder and bullet together until it is fired hopefully providing a gas tight seal when needed.Otherwise we would have rubber breach seals and needle guns!
 
Talking apples and oranges here, boys. I stated nothing about chamber finish. Chamber dimensions and finish are very important for good case life. I agree that the brass forms a seal, but it is exactly that seal that fails FIRST in an over pressure situation. When the pressures get high enough, it is the BRASS that flows and ruptures. That rupture may or may not destroy the rifle, depending on the strength & design of said action. I have been involved in several after-the-fact analysis of ruined rifles, and in every instance, the case is the weak link if pressures get too high. For example, if a reloader fires a round that is a few thousand psi over the max pressure in a given chambering, what will happen? The primer pocket will enlarge to the extent that the primer will fall out when the action is opened. No matter how strong the action is, the brass will fail, allowing hot gases to flow into various parts of the action. The swelling of the brass is what makes an action difficult to open when a load is fired that is too hot.Regards, Eagleye.
 
I am confused, why did Winchester use a thicker walled case in their 375Win?
I can understand why they changed the external measurments so they could not be interchanged with it's grandfather, the 38-55.

Does this mean hypothetically I could massage a 303 Brit case by whatever means it would take to get it in specs of the 308 Winchester and run the same pressure load as the 308 was designed for as long as it is in a strong actioned firearm?
 
Noel, get a P14 and go hard. Yep, it can work. I have run my 303 No4 to 7.62 standards using 150gr Hornady SP and H335. Spongy action leads to relatively short case life though.

Eagleye is right on about the brass. Most brass alloy used in cases will start to flow around 70,000psi (action are proofed at 100/120,000psi, sometimes more). It is like an escape valve for ambitious handloaders.

You will see some very obvious pressure signs long before the action goes kaboom. That assumes you don't dump 45gr of Red Dot into a 308 case just to see which fails first, the case or the action.

Jerry
 
Jerry, I am not just meaning loading up a 303 Brit to 308 Win velocities, but actually reforming the case to the same dimensions as a 308 case and then using it in whatever rifle was handy, chambered in the Winchester cartridge.

I realize it may not be possible to do so, but just to try to make the point that I wouldn't think that sort of use of a case would promote a long shooting career.

Thank you for the clarifacation, I should have worded my last post different.
 
22 Hornet to K-Hornet
6mm Remington to 257 Roberts
7x57 to 257 Roberts
260 Rem to 260 Rem Ackley Improved
6.5x55 to 6.5x55 Ackley Improved
25-06 Rem to 6.5-06
270 Win to 6.5-06
270 and 7mm Weatherby to 264 Win Mag
7mm Rem Mag and 338 Win Mag to 308 Norma
300 Win Mag to 308 Norma mag (better idea)
7mm Rem Mag & 338 Win Mag to 30-338 Win Mag
30-06 to 30 Gibbs
35 Whelen to 30 Gibbs
30-06 to 8x57JS
284 Winchester to 6.5-284
30-06 to 35 Whelen
30-06 to 8mm-06
8mm Rem Mag to 7mm STW
300 Weatherby Mag to 7mm STW
340 Weatherby Mag to 7mm STW
Probably a couple more I've forgotten about. Eagleye.
 
Pathfinder said:
If I was to reform a 7 mm remington mag case into 264 win mag would have to turn the necks or would the thickness be ok ?
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It will depend on the throat in your particular rifle, but and my bet would be that you would not have to turn the necks. IIRC, River Rat makes 264 from 7mm Rem, and years ago I formed some 257 Wby frfom 7MM Rem with no need to turn the necks.

you will know pretty quick. Just full length size one case, seat a bullet and see if it chambers freely. :)

Ted
 
TimC said:
6.5 swede into 7.5 MAS. So easy until they started selling the MAS brass and I bought a 6.5 swede so I have marked all my converted brass!
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I have got round this now by resizing al my 6.5/7.5 brass back to original 6.5. At least I didnt trim any!:D
 
7mm Rem Mag to 257wby

I recently purchased a 257wby and had a pile of 7mm rem mag new fired once range brass.

I've never tried reforming before but figured the brass was free so I'd give it a shot.

I lubed up the 7mm brass really good and slowly put it through my 257wby die.
It came out .25 cal but around the shoulder there were a bunch of small dents.
Figured that maybe the cheap ass brass was too soft so I tried it again with a piece of federal brass.
Same thing.

Any ideas? Is this normal?
 
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