Brass hardness

[CatShooter]

CatShooter,
Did you make a cast of the chamber of the original barrel on the .22-250 so the new barrel(s) were chambered to the same or almost the same dimensions? Sounds like the last two barrels had a little shorter chamber than the others because of the full length sizing step. Annealing and similar chambers must make a real difference in brass life along with sizing and load. Either that or Winchester was making REALLY good brass back then or at least that lot! lol !! At my last job I always used the "coat hanger" description to explain how brass was affected by sizing. "if you bent the coat back and forth in small amounts it lasted longer that if you bent the hanger back and forth in large amounts. That explanation was easy to understand. If you find your Industrial manuals let us know what you find out!
Thanks CatShooter!
Merry Christmas!
Phil

No cast, but the same folks did the rebarreling and their reamers are all cut very close to the same standard numbers.

The next to last was tight across the shoulder and the last was a few thou short.

Win brass is still very good, just not in comparison to the best of European brass. If I was limited to US brass, I would get Winchester every time. When I got the last rebarrrel to .244 on that 40XB, I waited got over a year for Winchester to make a run of 6mm Rem (244) brass - they do it every few years, and it is sold before it is made. I bought 1,000 pieces.

 

[Webster]

Cat, Nice work. We finally have real hardness numbers. You mentioned the case head hardness variation between cases probably depends on how they are made rather than alloy content. My take on this is that the case is formed by swaging a flat disc into a cartridge case in about five different swaging steps with an anneal of the entire slug after each step and a final neck anneal. This means that the perform and finished case are annealed many times. Does anyone know how the case preforms are annealed? I would think they are on a belt and continuously travel through a furnace with an inlet and outlet opening? What temp?

 

[CatShooter]

Cat, Nice work. We finally have real hardness numbers. You mentioned the case head hardness variation between cases probably depends on how they are made rather than alloy content. My take on this is that the case is formed by swaging a flat disc into a cartridge case in about five different swaging steps with an anneal of the entire slug after each step and a final neck anneal. This means that the perform and finished case are annealed many times. Does anyone know how the case preforms are annealed? I would think they are on a belt and continuously travel through a furnace with an inlet and outlet opening? What temp?

The head is formed in a series of punching (i.e. "pounding")... when the body is finely drawn, the upper section is annealed. At that point, they are usually stored until it is decided what they will become. Like 0.473" cylinder can be 30-06, 270, 25-06, etc.

The 0.473 machine runs all the time, the final calibers are made in batches when the market needs them.

Same with the 0.380" cylinder machine, etc.

 

[spclark]

Your $2,500 Ames Hardness Gauge, OUCH, that's a lot of money!

Yes it is but like anything you get what you pay for! Got to know how to use it too as well as calibrate and maintain it. You can have your very own:

http://m.ebay.com/itm/191420470182

- for a lot less $$ too!!

- and how they work:

http://www.worldoftest.com/amesmanual.htm

 

[CatShooter]

Your $2,500 Ames Hardness Gauge, OUCH, that's a lot of money!

Yes it is but like anything you get what you pay for! Got to know how to use it too as well as calibrate and maintain it. You can have your very own:

http://m.ebay.com/itm/191420470182

- for a lot less $$ too!!

- and how they work:

http://www.worldoftest.com/amesmanual.htm

Hmmmmmm the serial number is ground off. Wonder why?

 

[Shynloco]

Alex... the reason I didn't do Federal is I won't keep the crap in my place. I won't even pick it up at the range.

Cat,
I know of your technical prowess, so I'd be interested in why you believe Federal brass is crap? Years ago and before I started reloading and bought ammo across the counter (mostly .223 and .308 for a Sniper Rifle), I found the loads to be some of the most accurate shooting ammo commercially produced for the general public. Now after I did start reloading, time and experience taught me that Lapua and Norma were far superior, although that Federal brass was some decent and rugged brass for general hunting and pllnking and withstood abusive use. So I'm not here to say that Federal is a brass I'd use or recommend it's use in competitive shooting. I was merely wondering the hardness value of the Federal brass. Thx.

Alex

 

[CatShooter]

Alex... the reason I didn't do Federal is I won't keep the crap in my place. I won't even pick it up at the range.

Cat,
I know of your technical prowess, so I'd be interested in why you believe Federal brass is crap?

Alex

I have an M-24, 308 match rifle which is blindingly accurate. I started shooting Federal GM cases cuz I had 100 when I built the rifle. I weighed the cases and they all ran from 175 to 177 grains

I needed more cases, so I bought another 100. Shortly after, the rifle went into the toilet and groups with 175 SMKs went from <1/4" to >3/4" and sometimes an inch.

I was really troubled since it was the spring and I had registered for a serious match down south, and my spotter/partner was pumped on going.

I didn't have time to get a new barrel fitted, and went crazy trying to figure what was wrong. Then, I decided to weigh the cases (which were now mixed in with the first 100) The range of weights was now 154 to 181 grains... that's a 18% weight spread

So I tossed the bunch, bought 250 Winchester cases (tossed the split necks ) and all was fine.

That burned it with Federal and me!

 

[tgonza]

How about Hornady?

 

[Shynloco]

I didn't have time to get a new barrel fitted, and went crazy trying to figure what was wrong. Then, I decided to weigh the cases (which were now mixed in with the first 100) The range of weights was now 154 to 181 grains... that's a 18% weight spread

I can definitely relate to that as I've been down that road myself with some ridiculous weight spreads in brass and a weapon that otherwise shoots nice tight groups with "good brass." In fact, for the past several years I still check the weight of my brass and organize and shoot them according to weight, that by my standards, MUST be within 1 - 2 total grains in spread for the group being shot. So thx for the explanation as I suspected it was something like what you explained. I oft times wonders if the newer shooter even takes these types of variables into account in any discussion of accuracy. For myself, I've definitely learned to appreciate and examine every conceivable cause/variable when any previously proven load in a weapon goes south. Happy shootin!

Alex