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jaybic
04-13-2009, 11:22 AM
Hello,

I am going to make my first ever attempt at annealing cases and before I ruin a bunch of cases, I thought I might as a couple questions.

I am going to chuck up one of those Lee case holders that are used with the Lee case trimmer in my cordless drill and spin it while holding it in a butane torch for uniform heat application. Will this work as a decent heat sink? I am also not sure how high I should have the torch turned up and where in the flame the case should be. I also dont know exactly where on the case I should hold the torch.....neck....shoulder.....in between???

As I have read on other threads here, you should quench the case in water about the time the neck starts to turn a yellow or straw color so as not to over heat the case head. Red or orange case necks = too hot?

Finally, how do I know it worked or I did it right? Is there some kind of test a guy can do so he knows that the newly annealed cases are not dangerously weakened and are properly annealed?

Sorry for the oddball question. Maybe I am making something fairly simple into something unnecessarily complex but I just want to learn to do it right.:)

Thanks fellas,

jamie

Pete Wass
04-13-2009, 12:02 PM
That has not had anything done to it and compre what you have annealed to a virgin case or a once fired factory case might do. You want to see an area from the neck down below the shoulder colored the same as a virgin case or as close as you can get. Try your annealing in a darkened space with some dim light behind you so you can see what you are doing; sort of. You will need dark to see the color come up.

One of the nice features of the Ken Light machine is the hot water in the center of the wheel it acts as a stabilizing media so the cases do not need to be quenched after they go through the flames. Quenching doesn't hurt anything though.

vmthtr in green
04-13-2009, 12:24 PM
Why do cast bullet shooters quench their bullets? To harden them. Wouldn't quenching the brass do the same thing?

Mike

Jetmugg
04-13-2009, 12:47 PM
Brass cannot be hardened by a quenching operation. Brass is hardened by inducing "work" into the material. Brass is typically hardened by "cold work", which is mechanical deformation. Dislocation of the grain boundaries is responsible for the hardening effect seen in brass alloys. Applying cold work to a brass material actually makes the material stronger - at the expense of ductility.

Annealing the brass requires heating into a temperature range where the grain boundaries become mobile, and move back towards their equilibrium positions. Both over-heating and holding too long at temperature will cause grain growth, which will result in brass that is too soft and weak. Quenching in water immediately after heating is a means to stop grain growth and also to trap any impurities in the matrix of the brass, rather than allowing impurities to migrate to the grain boundaries where they will cause problems.

SteveM.

vmthtr in green
04-13-2009, 12:59 PM
Steve,
Thank you for that answer. I was under the impression from cas tbullet shooters that quenching would harden the brass.

Mike

Jetmugg
04-13-2009, 02:24 PM
Alloys of 2 or more metals can behave in ways that seem to defy common sense. Heat treatments that work for a particular family of alloys are inappropriate for other alloy families.

With respect to cast lead bullets - many lead/antimony alloys respond to quenching and aging (kind of like tempering) heat treatments where higher hardness is desired. Pure lead does not respond to these same treatments.

My formal education is in metallurgical engineering, so I "get into" some of these metals related discussions.

SteveM.

crb
04-13-2009, 03:32 PM
I sure like the molten lead method of annealing. Get the lead pot up to about 650 to 700 degrees, dip the case up to the shoulder for about 4 seconds and then quench in water. Wipe off any residual lead left on the case and go to the next one.

Seems to give excellent results without all the anguish involved in attacking your brass with an open flame.

John S
04-13-2009, 05:16 PM
I just anneled 300 7 BR T.N. cases that had been fired at least 15 time each.

I've been wanting to do this for a very long time, but always came up with some complex or darn right silly suggestions.

Go here: http://www.woodchuckden.com/

Order their anneling tip.

Stand cases up in 1/2 inch of water.

Place properly adjusted tip (blue flame no yellow) around the neck about where the neck and shoulder come together.

Hold there steady for 15 seconds (I use my shooting timer from Sinclair) knock case over in water and go on to next case and repeat.

No expensive equipment, No dark rooms, no is it red? or maroon?, no B.S. no tempi sticks that don't work etc, etc

The only suggestion I have is that you should be operating at room tempeture of 68 -70 degrees.

I cleaned the cases before anneling

After anneling I then bumped, then neck sized, then trimmed and deburred.

The proof is all bullets seat smoothly with the same pressure.

Larry in VA
04-14-2009, 12:45 AM
Varmint Al has an excellent write up on "Neck Annealing" on his web page. Check it out.... http://www.varmintal.com/arelo.htm#Anneal
Larry

gray wolf
04-14-2009, 08:28 PM
I can't afford a machine so what I do is use a deep socket that holds the case with a slight snug fit. Old chop stick stuck in the end for a spinner arounder. Propane torch,and heat the neck shoulder junction till the neck and shoulder turn a light blue--No red glow- then I quench in cold water.
This is to arrest the heat and keep the web area from getting to hot.
takes about 10 seconds for me. After they are cool they have a light straw
color at the neck and a little on the shoulder.
No lead will not harden if quenched---but the lead antimony ,Arsenic alloys used for cast bullets will harden some if quenched.
Correct on the brass--it hardens by work hardening. Heating and cooling will not harden it as it does for steel alloys.

GW.