Hornady 10mm Brass

glock20c10mm · 12-18-2010, 15:02

From what I understand, Starline Brass is a harder brass than Winchester Brass. And harder brass is supposedly better for full-power loads than softer brass, specifically for first time use when new.

Anybody know how the hardness of Hornady brass is compared to Starline or Winchester brass?

Craig

MinervaDoe · 12-19-2010, 17:08

I wish I could help you out with this one because it is an interesting topic.
I tried finding some data with a couple of Google searches, but nothing relevant comes up.
Hopefully, somebody with this type knowledge will drop by.
I have heard a number of people say that Starline brass holds up well.
I haven't reloaded my Starline brass enough times to comment.

crsuribe · 12-19-2010, 23:16

This thread needs some Kegs.

Kegs · 12-20-2010, 06:53

Thanks for your confidence, but the only brass I have ever reloaded has been Scharch.

Soon I will be relading some double tap nickel plated brass, which I will have to re-work up my loads since I expect these are going to change my formula a little (my suspicion is that they may not need as much powder).

glock20c10mm · 12-20-2010, 23:28

Quote:

Originally Posted by MinervaDoe

I tried finding some data with a couple of Google searches, but nothing relevant comes up.

I feel your pain. I searched somewhat extensively, and also came up with nothing. Hornady manufactures it for the retail market, and someone out there must know something, so I popped the question here. I figured someone in this forum must have at least had some experience with it before, but so far, no. May just take a while before someone with the knowledge comes across my question. Or not.

Good Shooting,
Craig

Atomic Punk · 12-20-2010, 23:37

could do a hardness test on them all. somebody may have what you need to properly do the RC hardness test. but you could build your own small drop tower and measure dent depths. you may not be able to figure out what the hardness of each is. but should be able to figure out where they all are in comparison.

**DWARREN123** · 12-21-2010, 01:14

I don't know about hardness but they look the same as Starline when fired in my G20SF. Have to look at the headstamp to tell them apart.
The big difference for me is cost, the Hornady is more expensive.

glock20c10mm · 12-21-2010, 08:43

Quote:

Originally Posted by Atomic Punk

could do a hardness test on them all. somebody may have what you need to properly do the RC hardness test. but you could build your own small drop tower and measure dent depths. you may not be able to figure out what the hardness of each is. but should be able to figure out where they all are in comparison.

Specifically on unfired cases, I think that's a perfectly good idea.

MinervaDoe · 12-21-2010, 11:47

Quote:

Originally Posted by Atomic Punk

could do a hardness test on them all. somebody may have what you need to properly do the RC hardness test. but you could build your own small drop tower and measure dent depths. you may not be able to figure out what the hardness of each is. but should be able to figure out where they all are in comparison.

I wonder if there would also be a benefit from weighing them.

After my PPC shoot last night, someone left behind a big batch of factory 9mm brass and it felt noticably tinnier and lighter than my own brass. Of course, I picked it up anyhow ...

glock20c10mm · 12-21-2010, 17:17

Quote:

Originally Posted by MinervaDoe

I wonder if there would also be a benefit from weighing them.

After my PPC shoot last night, someone left behind a big batch of factory 9mm brass and it felt noticably tinnier and lighter than my own brass. Of course, I picked it up anyhow ...

Interesting that is was that easily noticeable. What brand is your brass, and what brand was it that you found?

MinervaDoe · 12-22-2010, 16:23

Quote:

Originally Posted by glock20c10mm

Interesting that is was that easily noticeable. What brand is your brass, and what brand was it that you found?

I weighed the brass I found (including the primers) and it was actually heavier than some of the brass I fired. Go figure. My very subjective SWAG was wrong.
I was shooting the FC and CCI

PMC = 62 grains
S&B = 60.9 grains
FC = 59.2 grains
CCI = 64 grains

As to the amount of annealing and the quality of the brass, I think that gets back to your original question.

A Google search for "brass cartridge hardness" yielded promising results. Here is a sample from the first page:

Here is an article about annealing. It suggests a test which I believe will not accomplish what we are discussing here.
http://www.lasc.us/CartridgeCaseAnnealing.htm

On this site, some "machinists" discuss it. I found post #11 informative.
http://www.practicalmachinist.com/vb...-specs-205640/

MinervaDoe · 12-23-2010, 17:42

But wait, there's more ....
So after reading the articles at the above two links, we feel like we have more information.

Quote:

Cartridge brass can vary from 67/33 to 72/28 Copper Zinc alloy, with most brass being "70/30"

The Germans set on the 67/33 mix very early on,( 1880s) for use in all types of Firearms; but during WW II, the 72/28 mix was used for some Aviation Ammunition, due to its better hardness factors.

But upon doing more research, we realize that brass "hardness" is determined by two things: the percentage of brass and zinc and annealing.

More reading for your weary eyes:
http://www.gun-tests.com/performance/jun96cases.html

Quote:

Annealing brass makes it tougher and stronger, which gives you more life out of your handloaded cases.

Quote:

Annealing is nothing more than heat-treating a portion of the case and letting it cool. This process prevents the metal from being brittle.

Quote:

Annealing leaves the neck, the bullet-gripping portion of the case, soft enough to be cold-worked several times—by firing, then by resizing, again and again—but another annealing may become necessary later.

Here's a key point:

Quote:

Annealing softens the neck, to offset the cold-working and to retain the resilience of softer brass.

So, we have to ask if we are really looking for harder brass, when maybe brass which has been properly annealed may have longer life.

And finally, to go full circle (sort of) here is an article about a Hornady annealing kit.

http://blog.sinclairintl.com/2010/03...ealing-system/

MinervaDoe · 12-23-2010, 17:52

I also found this article about Making Brass the Starline Way informative.
http://www.shootingtimes.com/ammunit...910/index.html

Now that I feel so much better educated about brass, why does my head hurt?

glock20c10mm · 12-23-2010, 20:25

MinervaDoe,

Thank You for sharing your research!

The only thing I'll add, based on one of your last statements on whether or not harder brass is the way to go, is that I recall Mike McNett mentioning some time ago that new harder brass was best for full power 10mm loads.

I guess there's still always give and take. Now I just wonder where Hornady's brass fits into the mix.

Merry Christmas,
Craig

MinervaDoe · 12-23-2010, 20:40

You're welcome. Hopefully, someone will come up with some hardness measurements.