Split necks.

[4xforfun]

Loading for a friends 338 Edge. Custom min spec reamer (mine), Brux BBL. Redding type "S" bushing die....no expander, .002 neck tension. 91.5 H1000 behind a 300 Berger @ 2840. 215 primers. Bertrom brass. 2 firings.....50% split necks!!

I annealed the brass after the first firing with my Benchsorce. Called the distributer and he said that it is the first issue he has ever heard of .....with something like 200,000 pieces out on the market now.
He said that he will replace them...no problem. BUT..he also asked why I annealed the brass. I stated that I anneal EVERY piece of brass EVERY time I load it. He never questioned my abilities but seemed unsure of my practices.

So, I am trying to figure out if it was something I did wrong. Under annealing the brass would have ZERO effect on the brass one way or the other, and OVER annealing would make them soft and LESS likely to split. He said something about obviously quenching the brass. I am pretty sure that it is NOT NECESSARY to quench brass, as it has different qualities than steel.

Anyone have any Idea's? I still have 25 two x fired brass and 50 unfired from the same purchase. The 50 RUM brass for my gun has 7 firings on it with the primer pockets just starting to loosen and ZERO split necks.

Thanks,
Tod

 

[Ledd Slinger]

If you anneal for too long, the brass can become brittle. I only use ONE torch head on my Benchsource Vertex and set the flame as low as possible. Depending on the size of brass, it generally takes me 10 seconds per piece before the wheel cycles. I figure this time out by watching it in total darkeness using cull brass in case i mess up. At the very first sign of the brass beginning to "glow" red, i want the wheel to cycle it out of the flame.

If the brass is fully glowing red and still turning in the flame, it is being annealed too long and theres a good chance its weakened and ruined.

PS: i do not quench the brass in water and have never experienced issues like you are seeing.

 

[4xforfun]

I run two bottle gas torches and I run the Edge brass 5 seconds. I test every new cartridge with 650 and 400 degree templaque.

 

[Webster]

Brass does not become brittle from over annealing. Just the opposite. It becomes softer and it has more ductility and less tensile strength. I don't understand why he has split necks. The necks should only split from getting harder from cold working. 91.5 grains of powder, sounds like a pipe bomb. If the primer pockets are getting loose the load has pressures high enough to deform the case head. Your pushing the limits. Is the OP sure he is annealing long enough or at a high enough temperature. The original OP stated under annealing wouldn't cause problems. It does, with each firing and under anneal the brass continues to work harden and lose more ductility.

 

[Dusty Stevens]

Think about how many rounds are fired each year without annealing. It is one of those things that a few target shooters do that i think people take too far. Its one of those things that if done perfect itll give you more consistent neck tension that will help you on some occasions shooting groups in competition. If done wrong it wrecks the brass and you just about gotta be a metallurgist to know if it was done right (most cases you wont know if its wrong or right). So if youre 100% perfect in your annealing your neck tensions are consistent. If you underanneal you just helped bernzomatic butane stock. If you overanneal you get case failure whether it be split necks or worse- case head seperations- dangerous!!!
Ill get off my soapbox now. Just remember if you dont anneal you may not have consistent neck tensions- go see if you see it on your particular target.

 

[Sheldon N]

May just be too hot of a load. Quickload puts pressure at 68k PSI if your OAL is long at 3.8, and if your OAL is the standard 3.6 inches then you are somewhere near 77k PSI.

What's your OAL and barrel length?

 

[Patch700]

Is it possible that there is a discrepancy between assumed neck dimensions of the chamber and actual neck dimensions? Perhaps the actual neck dimension is substantially larger than assumed an over sizing of the necks is happening with each loading... IE: actual neck dia of chamber is .010" or even larger than the bushing being used in the die. Possibly necks were turned when this wasn't needed?

Would have to agree with Websters postings above as a possible culprit as well.

Good luck

 

[savagedasher]

I would Google brass . You will find brass has many components in it the % of components used in making it gives strength along with it ability to be worked and or its use. Not saying the brass type is wrong for it use .
but it can happen.
Brass is an allow primary made from copper and zinc. The blend % of each give different results in it recommended use.
Annealing is any heat treatment in which the microstructure are altered. Annealing of metals only soften or increase its ductility . The time that it is exposed and the temperature determines the results .
Back to the neck splitting it can be the brass make up. But I have found it normally cased from over working the brass or it can be annealing but you sad it was done ever time . I would check what the neck size of the fired brass is and what the size you started with. If it is over .004 I would suspect that is the problem .
Larry

 

[4xforfun]

Nothing assumed here. I have the reamer in my hand. My measurments are EXACTLY the same as on the print.
Reamer.... .3715 neck, .242 freebore, 1.30 degree lead
loaded round neck diameter.... .366.

Fired round neck diameter.... .370

loaded round OAL.... 4.08"

Now, that is a little more neck clearance (.0055) than I usually run (.003), but the reamer was made based on the Rem 300 RUM brass..the only brass available at the time. The Bertrom brass is a touch thinner. If this is deemed the problem I can easily have Kiff re grind the reamer .002 less and set the chambers back. But, this would eliminate using Rem 300 Rum brass. Also, .0055 clearance on a case this big is statistacly not much different than having .003 on a 6mm cartridge.

91.5 is NOT A "PIPE BOMB" !! It ( the load and the velocity) is right in there with every other edge shooter's loads that I have ever heard from. Gun (BAT "M") 30" Brux was taken to 95 grains before any PSI signs appeared. With my Edge I ended up using the exact same load with REM brass and got 7 firings on the brass. The PP's are just now starting to get a little loose.

 

[savagedasher]

Nothing assumed here. I have the reamer in my hand. My measurments are EXACTLY the same as on the print.
Reamer.... .3715 neck, .242 freebore, 1.30 degree lead
loaded round neck diameter.... .366.

Fired round neck diameter.... .370

loaded round OAL.... 4.08"

Now, that is a little more neck clearance (.0055) than I usually run (.003), but the reamer was made based on the Rem 300 RUM brass..the only brass available at the time. The Bertrom brass is a touch thinner.

91.5 is NOT A "PIPE BOMB" !! It ( the load and the velocity) is right in there with every other edge shooter's loads that I have ever heard from. Gun (BAT "M") 30" Brux was taken to 95 grains before any PSI signs appeared. With my Edge I ended up using the exact same load with REM brass and got 7 firings on the brass. The PP's are just now starting to get a little loose.

The question is then the brass your using how much are you working it . Nothing else matters
Larry

 

[Sheldon N]

That's a little more reasonable in terms of OAL and load, but you've still got to be 65k+ PSI to get 2840fps out of a 30" barrel. Not a pipe bomb, but I could see how it might be harder on case necks with the reamer being designed for thicker brass.

Maybe try a couple of test charges at 88-89g and see if the problem with case neck splits continues?

 

[savagedasher]

That's a little more reasonable in terms of OAL and load, but you've still got to be 65k+ PSI to get 2840fps out of a 30" barrel. Not a pipe bomb, but I could see how it might be harder on case necks with the reamer being designed for thicker brass.

Maybe try a couple of test charges at 88-89g and see if the problem with case neck splits continues?

Wouldn't depend on the powder used. And if your using free bore. Larry

 

[Sheldon N]

No connection between pressure and split necks? I thought that was one of the potential indicators.

 

[savagedasher]

No connection between pressure and split necks? I thought that was one of the potential indicators.

Normally the base of the case is where you see pressures first Like flattened primers or blown out primer holes. I locked a bolt up from the case setting in the sun. But the neck was fine. Larry

 

[4xforfun]

Nothing assumed here. I have the reamer in my hand. My measurments are EXACTLY the same as on the print.
Reamer.... .3715 neck, .242 freebore, 1.30 degree lead
loaded round neck diameter.... .366.

Fired round neck diameter.... .370

loaded round OAL.... 4.08"

Now, that is a little more neck clearance (.0055) than I usually run (.003), but the reamer was made based on the Rem 300 RUM brass..the only brass available at the time. The Bertrom brass is a touch thinner.

91.5 is NOT A "PIPE BOMB" !! It ( the load and the velocity) is right in there with every other edge shooter's loads that I have ever heard from. Gun (BAT "M") 30" Brux was taken to 95 grains before any PSI signs appeared. With my Edge I ended up using the exact same load with REM brass and got 7 firings on the brass. The PP's are just now starting to get a little loose.

The question is then the brass your using how much are you working it . Nothing else matters
Larry

The numbers above tell you EXACTLY how much I am working the brass. I guess the number I omitted is the sized case neck diameter...... .364. I am using a .367 bushing to get this, which makes no sense at all to me. But I also have a .365 and a .364 bushing, and the FELT neck tension on the press handle when seating a bullet is a whole lot more with the smaller bushings. This gave me some verticle at 1000+ yards. The .366 bushing took care of most of the verticle. I know that this is not very "scientific", but feel is the only test method I have.

 

[josebd]

ive always quenched in water after annealing!

 

[4xforfun]

No connection between pressure and split necks? I thought that was one of the potential indicators.

No connection.

 

[josebd]

got this off of 6mmbr.com
Unlike steel, which will be made harder when it is cooled rapidly, brass is virtually unaffected when it is rapidly cooled. Annealing brass and suddenly quenching it in water will have no measurable effect on the brass. Cartridge cases are made of brass. When cartridge cases have been reloaded a number of times, the case necks become harder. Annealing will return the cartridge case necks to their factory original state.

 

[4xforfun]

got this off of 6mmbr.com
Unlike steel, which will be made harder when it is cooled rapidly, brass is virtually unaffected when it is rapidly cooled. Annealing brass and suddenly quenching it in water will have no measurable effect on the brass. Cartridge cases are made of brass. When cartridge cases have been reloaded a number of times, the case necks become harder. Annealing will return the cartridge case necks to their factory original state.

+ 1 on this. Also, the manufacturers of the annealing machines that I have looked at also state the same info.

 

[savagedasher]

got this off of 6mmbr.com
Unlike steel, which will be made harder when it is cooled rapidly, brass is virtually unaffected when it is rapidly cooled. Annealing brass and suddenly quenching it in water will have no measurable effect on the brass. Cartridge cases are made of brass. When cartridge cases have been reloaded a number of times, the case necks become harder. Annealing will return the cartridge case necks to their factory original state.

Your correct When quenching the case all you are doing is changing the time exposed to the heat.
Larry