Brass annealing quetion

[Tinker]

Hello,

Figured this would be the place to find my answer.

I have a .410. Shells for it are pricey. Found a web article about making (annealing and fire forming) reloadable solid brass casings from other caliber shells. .303 British is cited. He gets to the point were he anneals the cases in molten lead and then drops them in cold water. This is to be followed by fire forming with Cream of Wheat.

Understand that I have never reloaded any kind of shell and my only experience with annealing is with steel. When you anneal steel you don't quickly cool the item. You let it slow cool. It seems to me that brass would be the same way and quick cooling would harden the brass to be fire formed. Can anyone shed light on this? Thanks.

 

[mete]

Steel is steel and brass is brass. Annealing of brass starts at about 450F and since there is no transformation in fast cooling like there is in steel you can slow or fast cool whichever you want. You never want to anneal the head or base of the case ,only the neck and shoulder. A more convenient method than handling lead is to put the cases in a metal tray with water up to just below the shoulder. In subdued light ,use a propane torch to heat the cases one by one.As the case glows red tip it into the water and go to the next one.

 

[DR]

In a very small nutshell: steel changes its crystal structure as it changes temperature. With steel, letting it cool slowly lets the steel change its structure to a softer one. Quenching changes the temperature quickly enough that not all of the harder crystals formed at the higher temperature have time to transform to softer ones.

With brass there isn't the same concern. it's the heating that does the annealing. Quenching just gets it back to a workable temperature quickly and lessens scale on the brass. You don't have to quench to make it soft.

So, yes, it sounds counter-intuitive but the instructions you found are spot on. Another way to do it is to stand the cases up in a little bit of water. Heat the necks with a torch then knock them over into the water when they get hot enough. That won't anneal the base and it may take a little bit of practice to see how much to heat them.

 

[Tinker]

Thanks for the information. I will try the annealing process you guys mentioned. Sounds less tricky than using the lead.

In the article the author mentions that .444 Marlin shells can be used just as they are. The only drawback is that these will only make small, low power .410 shells. That will work perfectly for some of the small low power rat shots I want to make. If I want longer hunting shells I will have to use the .303Br , annealed and fireformed.

This will be fun to try.

 

[Ross]

The .444 Marlin case is nominally .003" longer than the .303 British, and the British will probably recede slightly upon fireforming. The Krag is a little longer.
CBC (Magtech) makes .410 brass. Graf has it for $13.39 per twenty-five. It has large pistol Boxer primer pockets. Other sizes I've used (12 and 24 ga.) have been of excellent quality. Do not get Berdan primed cases. CBC Berdan shotshell primers are frail, and are the only ones presently available in the U.S.
Cheers from Darkest California,
Ross

 

[Tinker]

Ross,

Shoot, for that price I'd be doing OK to just go with the .410 readymade brass. You got a URL for Magtech?

 

[Black Snowman]

http://www.grafs.com/ to buy the brass. I'm not sure if it's even listed on Mag-Tech's site. Which is http://www.magtechammunition.com/