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rtracy2001
08-27-2009, 04:14 AM
My dad reloaded for years, and never once did I see him anneal a case. Seems he was in the reserves, so he brought home military cases every month. As such he just threw the whole lot away whenever they started to crack.

Dad isn't with us anymore, and I don't have the luxury of free military brass every month, so sooner or later I will need to anneal some cases (at todays prices I can't afford not to).

My dad's old Lyman manual gives the following instructions:

1. Place brass head down in a shallow pan and fill the pan with water until 1/2 the case is covered.

2. heat the necks with a torch until Cherry red.

3. Tip the cases over into the water to cool.

now normally I wouldn't think to question the manual that much, but in engineering school they taught us that the faster the quench the harder the metal becomes. They also told us that a water quench is a very fast quench, air is slightly slower, and furnace annealing is the slowest.

the question is "is tipping the cases over into the water correct, or should I do something different?"

Thanks
Ray

versifier
08-27-2009, 02:46 PM
There are several ways handloaders anneal their cases, but first, there is one thing that should be made clear. Unlike ferrous metals, copper based alloys do not harden when quenched, they only work harden. Heating both kinds softens them (annealing), but only ferrous metals harden in quenching. So why do it? Quenching the cases prevents over annealing so they do not soften to the point that they can no longer hold a bullet firmly.

It takes a bit of practice to get to know how much heat to apply, so start with a batch that you don't care about until you get a good feel for it. Go too far with a few of them so they are too soft, then FL size and try to seat a bullet in them so you understand how they will look and act and remember the difference between the bright glow of "too much" and the duller glow of "just right". This sounds a lot more complicated than it actually is, but as with anything, a little practice and it will become much easier to do.

The method that seems to work best for me is to use a propane torch with disposable cylinder, hold the case in my bare hand and rotate it so that the blue cone that is the hottest part of the flame contacts the neck/shoulder junction. After just a few seconds and a couple of rotations, the case warms enough that it becomes uncomfortable to hold, at which point I drop it into a water-filled coffee can. If done with the lights low, you can see the neck area just barely begin to glow. This method does not completely anneal the neck, but it is just enough for the brass to regain its elasticity.

The idea of setting the cases in water is to prevent you from annealing the case head, which would weaken it to the point it could not withstand chamber pressure. It works quite well, but it is still easy to get the necks too hot (I think cherry red is going too far) and ruin them. Once you get a feel for just how red to let them get, that way is faster than the one I use, but I lose no brass. At most I will do fifty cases at a time, but if I had to do a lot more I would probably consider something more elaborate to speed things up.

Thre other thing you need to be aware of is how to know when the cases actually need to be annealed, and this can vary with the lot of brass, how hot the loads are that you use, the shape of the chamber compared to your sizing die, and the method of sizing you use. The general rule is to anneal when the neck loses enough tension that it doesn't spring back after sizing to tightly hold the bullet. If you wait until the necks are cracking, you will ruin a lot of cases. That said, with a tight-chambered rifle and neck sizing, it is not unusual for me to get a dozen or more loadings out of a rifle case (FL sizing ever fourth or fifth time to set the shoulders back) before annealing is necessary. I do not load hot and will choose a powder/bullet combination that will give optimum accuracy in the middle of the charge table. OTOH, there are a bunch of milsurps I load for that have very loose and worn chambers, so the brass fired in them gets stretched more in the firing/sizing process, and their cases need annealing much more often. IME, the .303Brit SMLE's can be the hardest on brass, needing FL sizing at least sizing every other loading and annealing every third or forth. Some handloaders prefer to lightly anneal their milsurp cases every loading, but I think that's going a bit far. The more the brass gets worked, the quicker it hardens to the point where it will no longer spring back. When you learn how often it needs to be done in a particular rifle, you can prolong the case life by at least 4X. If your loads are mild, they won't loosen the primer pockets, which is what usually kills cases - there's really no way to save them when that happens, but as long as they are tight, you can keep annealing the neck and shoulder when needed and keep your brass in circulation much longer.

runfiverun
08-28-2009, 02:20 AM
try here this should fully splain it.
http://www.lasc.us/CartridgeCaseAnnealing.htm

rtracy2001
08-28-2009, 03:30 AM
Ah, the critical piece of information that I was lacking. "Engineering classes don't talk much about brass (or any non-ferrous metals other than aluminum)" I remember that now of course.

OK, sounds like I just found a use for all those odd cases that I manage to pick up at the range.

Thanks all.

versifier
08-28-2009, 04:23 AM
r5r,
That is a GREAT article. I have copied it into my e-library for future reference. Thank you for posting the link.

Jim_Fleming
08-28-2009, 10:40 AM
Here's a good video of the process:

Annealing Brass: http://www.youtube.com/watch?v=CbRdJqyFDGY&feature=related

runfiverun
08-29-2009, 02:47 AM
there is another one at 6mm Br but i think that one explains it easily enough.
i have to remeber it by brass is the opposite of lead.

Swede
09-27-2009, 12:41 PM
I have to say that looks easy enough. Also looks like an electric screw driver would come in handy.

Jim_Fleming
09-27-2009, 04:13 PM
You're right, Swede, in the video, Ammosmith directly mentions that he normally uses an electric screwdriver, but because of the noise of the screwdriver he couldn't use it, and narrate the video.





I have to say that looks easy enough. Also looks like an electric screw driver would come in handy.

Milanodan
09-29-2009, 11:43 PM
I just stand a bunch of deprimed cases in ~2" of water (30/06 case length) in an old metal pie tin. Then I play the propane torch flame on the necks/shoulders for ~10 sec. ea., then tip them over with the torch end.

I can anneal ~50 cases in 7 or 8 minutes. Haven't had a neck split on me in many years.

Jim_Fleming
09-30-2009, 02:29 AM
And that's exactly how it should be...!

I just loaded up some test loads for my .270, and I noted that the cases 'felt' tough when I was seating bullets... I need to do exactly that same thing...





I just stand a bunch of deprimed cases in ~2" of water (30/06 case length) in an old metal pie tin. Then I play the propane torch flame on the necks/shoulders for ~10 sec. ea., then tip them over with the torch end.

I can anneal ~50 cases in 7 or 8 minutes. Haven't had a neck split on me in many years.