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oldandslow
05-26-2018, 07:08 AM
Greetings,

Since I'm doing a load workup for my 30-06 I want to have the cases as consistent as possible. This means I need to anneal the cases which also prolongs brass life. During the last "great bullet hording" when it was impossible to buy bullets I started casting for rifle, pistol and shotgun slugs.

In researching brass annealing I find a bunch of data on gas torch annealing but only a bit of hard data on lead pot annealing- I needed specifically the temp. and number of seconds to keep the case in the lead melt and the prevention of lead sticking to the case.

I did some testing on Winchester 30-06 cases, 9 times fired with annealing every three firings. I'll present the conclusions first and the pics and data last.

1. Lead dipping for 8 seconds into a 15 lb. Lyman pot with a surface temp. of 750-775 deg.F and then wiping the warm case with a cotton rag to remove all the residual lead on the case necks gives an acceptable anneal of the case neck and shoulders and the first 1/8 to 1/4 inch of the case body. The cases were dipped to the shoulder-body junction.

a. this result works well when the cases are uncleaned and tarnished and the fired primer in place. There was no leading on the interior neck. Cases were dropped in cold tap water after annealing to limit heat transfer to the case head.

2. Using new cases without a primer resulted in the most leading externally and internally.

https://i.imgur.com/BoIoLuw.jpg?1
https://i.imgur.com/e2BL8IZ.jpg
https://i.imgur.com/TklROeQ.jpg
https://i.imgur.com/GTswqRN.jpg
https://i.imgur.com/yUXOE38.jpg

Data- 1. It took 30 minutes to get the pot up to temp.- measuring 775 deg.F at the bottom of the pot and 750 deg.F in the first inch of depth (measured with a RCBS dial thermometer). The air temp just above the lead surface was 295 deg.F.

2. I tried various case coatings to decrease lead coating of the cases- namely motor mica, imperial sizing wax and 10-40 oil. All worked to some degree but the best result was wiping off the case with a cotton rag just after dipping.

3. The cases were held in place over the lead pot with a leather welding glove.

The next experiment will be with 450 deg.F Tempilaq to record how the dip times affect the length of annealing down the case body.

Since I had difficulty finding specific info on lead dipping times and temperatures I hope this will provide a starting point for others. Lead dipping has the advantage of a known repeatable temp. and symmetric annealing around the case neck without the guesswork of eyeballing a case color change as with flame annealing. Best of all is that I get to melt lead again which had stopped due to affordable bullets now being available.

best wishes- oldandslow

Dusty Bannister
05-26-2018, 08:52 AM
I think the degree of success will depend upon the diameter of the case mouth and the size of the case being annealed as well. When I was doing some 223 to convert to 6MM TCU, I found the temp of 750 for a count of three did the job for me. But while the cases were left dirty, I had to remove the primers or the lead did stick in the neck as a plug. Maybe a longer heat time would have cured that, but it was a problem I was able to avoid. I used a wood holder, to grip the case by the bases and when the anneal time had passed, struck the holder while holding the case tightly, to strike or shake off the loose lead sticking to the case. Then drop in water.

If I were doing it today, I would do the same thing, but run the cases through the SS wet pin cleaner to knock off any specks of lead on the inside or outside of the cases after annealing. Grungy cases seemed to work best to prevent lead sticking. Dusty

jdfoxinc
05-26-2018, 09:03 AM
Carbon is an "anti-flux". Graphite was used by copper smiths to keep tin from adhering to surfaces of cook ware that were not to be tinned.

popper
05-26-2018, 09:43 AM
Just use the torch and fingers - cleaning the lead off the necks is a pain.

bangerjim
05-26-2018, 02:10 PM
Nice post, but for me, a good old propane torch flame is fast and easy.

And now that I use PC for every boolit I cast (totally elimiating leading in all my guns), I do not want to add leading back into my scheme of things.

Thanks for the alternate ideas.

Banger

Nueces
05-26-2018, 02:38 PM
Good info and well presented.

Rcmaveric
05-26-2018, 05:57 PM
I want to try the hot sand method, but I normaly do the dark room with fingers torch method.

http://www.texas-mac.com/Annealing_Case_Necks.html

Walter Laich
05-26-2018, 08:59 PM
I just ordered an annealing kit that uses melted salt.

will report once I've given it a test drive

http://ballisticrecreations.ca/

DerekP Houston
05-26-2018, 09:19 PM
nice technique and thanks for sharing the results! I've been toying with annealing my 30-06 brass and I could pull this off without any additional equipment.

therealhitman
05-27-2018, 12:14 PM
Well presented. I have been planning on at least trying this method for years but still haven't gotten around to it. Maybe soon now that you have put the bee back in my bonnet.

popper
05-27-2018, 12:35 PM
For me, annealing is a waste of time. I don't shoot unobtanium cases, long range or competitive. If I can shoot MOA 50-200 with cast, unsorted range pickup, no trickling, unweighed bolits - I'm good to go.

iMigraine
05-27-2018, 11:04 PM
I can see Annealing to preserve your rifle brass. At least that's my only real reason that I aneal.

turtlezx
05-27-2018, 11:18 PM
lead pot annealing works well and need nothing you dont already have was able to save 60 year old mashburn 218bee brass by this method