Annealing Case Necks Experiment

[texasmac]

Hey guys,

I was annealing a batch of brass today and thought I’d run a little experiment to determine the appearance of different brands of brass when properly annealed. The photo is the before and after annealing results of brand new Remington, Winchester and Starline. Although listed as .45-90, the head of the Starline case to the right is actually stamped 45-2.6

As noted, 750° Tempilaq solution was used inside the case necks to determine the correct heating duration and temperature to ensure the necks were not over heated. I have done a good bit of annealing and experimenting since purchasing a Bench Source annealer and have formed some opinions. One is that many shooters over anneal, which is generally not a dangerous situation as long as the head area does not get too hot and soften. But it can shorten the life of the brass and have other negative results. Note the subdued color changes of the necks. The vivid bright rainbow of colors seen in many photos of annealed brass is not evident but you can see the color change.

For more info on annealing case necks, see the following article: http://www.texas-mac.com/Annealing_Case_Necks.html

Wayne

http://i47.photobucket.com/albums/f165/RealTexasMac/NewvsAnnealedBrass_zpsbc0335ca.jpg (http://s47.photobucket.com/user/RealTexasMac/media/NewvsAnnealedBrass_zpsbc0335ca.jpg.html)

[kokomokid]

I never feel like I get a uniform anneal from case to case and have watched for info on using a Lee melter and dipping case necks in 750* saltpeter. If old polished cases would change color like new ones I would have no problem. LB

[rattletrap1970]

When I anneal I fill a pan with water up to where I want the annealing to stop. Then place my decapped clean brass in the pan. Then I dim the lights till I can just see what I'm doing. Then I heat the case till its just a tad more orange then red and let em cool.

[montana_charlie]

Then I heat the case till its just a tad more orange then red and let em cool.
When they were only red they were already hotter than necessary.
Blue is the color to look for, and it is a lot cooler than red.

CM

[rattletrap1970]

Hmm, I'll have to try that. I'm gonna pick up one of those infrared non contact thermometers to periodically check till I get a feel for it.

[texasmac]

Hmm, I'll have to try that. I'm gonna pick up one of those infrared non contact thermometers to periodically check till I get a feel for it.

It's cheaper & easier to use 750° Tempilaq solution. A dab on the inside of the neck of a few cases until you get "feel" is the way to go. It's available from several sources & will wash off if you don't bake it on too hard.

Or you could anneal in a dark room until the neck shows the 1st hint of glowing red, which is a good technique and should work fine, but can result in overheating the brass if you’re not careful and paying close attention. The cases should be rotated and the necks heated with a propane torch. Use a power drill and hold the case in a standard socket slightly larger than the case. Stop heating when the case neck shows the 1st hint of red. You can dump them on a wet towel or in water to speed up the cooling process but it's not necessary. Quickly cooling brass will not harden it as it does other metals.

Wayne

[John Boy]

Stop heating when the case neck shows the 1st hint of red. Wayne, this a color that is past the color to anneals in the 625-650 degree range. The cases should show a bluish-green color ... the stop

[ColColt]

My .222 Lapua Match cases show a perfect annealing by the factory. The color is a slight greenish from the case neck to just past the shoulder.

[montana_charlie]

Here's a video of a guy annealing to a blue color, doing it by eye, and not requiring a dark room.
http://www.youtube.com/watch?v=kgD5D0Wzu-c

CM

[MattOrgan]

I've been through the dull red coloring while the case is in a pan of water. Generally the case ends up dead soft which isn't helpful for anything. Have tried dipping cases in molten lead and burnt my fingers and had inconsistant results. Finally sprung for a bottle Trmpilaq. Made a case holder with a rod and a short piece of pipe. Put a stripe of 750 Tempilaq inside the case mouth. Hold the neck/shoulder junction or the last 1/4-3/8 inch between two propane torches. When the Tempilaq goes front blue to black, dump the case on the bench.The brass is rejuvenated and you get the factory colors shown by texasmac. My 38-55 brass is in its 15th loading and crimping (3rd annealing) and is like new. The wonders of the scientific method.

[texasmac]

Wayne, this a color that is past the color to anneals in the 625-650 degree range. The cases should show a bluish-green color ... the stop

John,

The following is from my article on annealing case necks:
http://www.texas-mac.com/Annealing_Case_Necks.html

Annealing brass depends on both time and temperature. Cartridge brass can be annealed at temperatures as low as 480° to 490°F but will require an extended time (hours) to fully anneal. Even at 600° it may take an hour or more and the complete case would be annealed, not just the neck, resulting in a very unsafe condition. If the head is annealed even slightly, it can fail and blow apart when fired. The solution is to quickly raise the temperature in only the neck area to a range of 700° to 800°F, at which point the neck is fully annealed. Since the high temperature is only applied for a very short duration, typically 3 to 4 seconds, the case heads will not exceed 450° unless the cases are shorter than about 1.75”.
==================================


Here are some more articles and the suggested annealing temperature:

750°F http://www.annealingmachines.com/how-to-anneal.html

660°F http://www.gun-tests.com/performance/jun96cases.html

750° to 800°F http://www.6mmbr.com/annealing.html

650° to 700°F http://bisonballistics.com/articles/the-science-of-cartridge-brass-annealing

750°F http://www.cartridgeanneal.com/

750° to 800°F http://www.kenlightmfg.com/cartridgecaseannealer.htm

Finally, based on a good bit of experimenting, I stand by my previous comment that one can hand anneal in the dark until the neck shows the 1st hint of glowing red, which is what happens when using 750° Tempilaq as an indicator. And I do mean the FIRST hint of red, which may be hard to detect. Remember, I'm using an automatic annealer and can watch the necks closely. Identifying the 1st hint of glowing red is a subjective decision. If the neck clearly glows a dull red than they have been over heated. I do agree that if 660° is the upper limit than the neck will not get sufficiently hot to start glowing red, but I've chosen to go with 750°. BTW, the necks are in the torch flame about 3 seconds.

Finally, I have tested the annealed necks for hardness using the crushing method with pliers. After annealing they are still hard

Wayne

[Riqrob]

I've had good consistent results by soaking my brass in lemon juice (or citric acid solution) to change surface oxidation back to brass. The brass will then turn bright blue when proper temperature is reached using a socket as a holder.
Rick

[EDG]

There is a color of light silver-blue that corresponds to about 610 degrees F. I have been using that temperature for about 20 years and have never lost a case. That includes heavily formed cases. I use about a 3/4" inner blue cone on a propane torch. I keep the case spinning and run it into the flame with the case neck about 1/2" from the tip of the blue cone. I move the flame from the case mouth down to about 1/4" past the shoulder or bullet base. It takes a quick count of 1,2,3,4 and it is done. You will know the proper silver blue when you see it because it actually looks wet.

[eljefeoz]

Newby Query:
what if you UNDER anneal?
TIA

[Wally]

A very cool blue green color as Johnboy mentions is where you stop, I anneal after every firing, Chrono Numbers, accuracy at 800-900-1000 yards to 1 mile proves too me beyond any doubt that it does not hurt a thing!

KW




The Lunger

Kenny, as you anneal after each shooting what king of case life to you get when you do? I had thought annealing after 4~5 firings will give you the longest case life.

[Ed in North Texas]

I never feel like I get a uniform anneal from case to case and have watched for info on using a Lee melter and dipping case necks in 750* saltpeter. If old polished cases would change color like new ones I would have no problem. LB

Did you see the May thread with the post about doing that very thing. Battlerife, from Alberta, Canada posted pictures and I seem to remember a video, along with his description of Potassium Nitrate salt bath annealing with the inexpensive Lee pot.

http://castboolits.gunloads.com/showthread.php?153620-Annealing-Setup

[Ed in North Texas]

Newby Query:
what if you UNDER anneal?
TIA

Then you don't have brass which is any softer than when you started. If new brass, it will be whatever the manufacturer made it. This is an issue with some brass, like Starline, where the brass might be used with either smokeless loads, or Black Powder loads. Starline recommends some of their brass (Black Powder caliber brass like .45 and .50-70, etc.) be annealed before use with Black Powder because the lower pressure load might not cause the case to obturate (seal) completely. Usually only results in really dirty brass outside and maybe a bit lower pressure and velocity. If your brass was really hard (shot and reloaded lots without annealing) then the life of the brass will be shortened - but nobody can agree on how much, or whether it really makes a lot of difference in case life if you are shooting hot loads all the time.

Hope that helps.

[detox]

I once read an article in SPG's Black Powder magazine on how to anneal cases in molting lead (20/1 alloy). The simple process worked very well back a few years ago when i tried it. Now i cannot remember how to duplicate process without lead sticking to my brass.

[kokomokid]

(detox) I tried it long ago with bullet alloy, I guess the tin made it solder to the cases. I annealed some last week with the room almost pitch black with ok results. LB

[kokomokid]

ED north tx That was the lee pot anneal I was looking at. Don't know how toxic saltpeter is in a molten state but I guess we breath in some every time we shoot. I think it would be uniform from case to case but may need another cleaning step. LB

[Springfield]

I anneal by dipping my 44-40 cases in my casting lead. The lead just peels off the cases, but I am lazy and just tumble them to remove the lead. I had some used cases I bought(were WAY more used than described in the ad) and about 2 out of 10 were splitting when reloaded. After the annealing about 1 in 75 split, so I know it helped.

[John Boy]

Wayne, I read this in the last link you posted and for the love of me, I don't understand it ...

If cases are heated to about 600 degrees (F) for one hour, they will be thoroughly annealed -- head and body included. That is, they will be ruined. (For a temperature comparison, pure lead melts at 621.3 degrees (F)).

The critical time and temperature at which the grain structure reforms into something suitable for case necks is 662 degrees (F) for some 15 minutes. A higher temperature, say from 750 to 800 degrees, will do the same job in a few seconds. If brass is allowed to reach temperatures higher than this (regardless of the time), it will be made irretrievably and irrevocably too soft. Brass will begin to glow a faint orange at about 950 degrees (F). Even if the heating is stopped at a couple of hundred degrees below this temperature, the damage has been done -- it will be too soft.
http://www.kenlightmfg.com/cartridgecaseannealer.htm

The author writes temperature as factor of time except the 750 to 800 for seconds. But on the flip side he says 600 for an hour but the case will be ruined.

So guess I'll have to continue with the old fashioned way: bare handed with a flame spreader propane torch - spin the case with the thumb & index finger in low light - heating from just above the shoulder for those calibers & the seated bullet depth for straight cases ... up to the mouth. When the area turns a bluish green (625 - 650), the case is laid down on a cotton towel to cool ... not dunked in an ice bucket which does not cause brass metal to be annealed.

All the cases are initially annealed and the cases are only mouth expanded 0.001 to 0.002 for the bullet being used and go back in the same recipe box including the same bullet diameter so they are not work hardened aka FL sizing. For those cases, if there is a distinct decrease in accuracy, then they are annealed again as an indication the mouth is not adhering correctly to the chamber wall

Granted there are Chevy's Chysler's and Ford stated ways to anneal but I can anneal a 100 pieces of brass the old fashioned bare handed way in less than 20 -30 minutes and am satisfied they are properly annealed

[texasmac]

I once read an article in SPG's Black Powder magazine on how to anneal cases in molting lead (20/1 alloy). The simple process worked very well back a few years ago when i tried it. Now i cannot remember how to duplicate process without lead sticking to my brass.

detox,

When I used the technique I first dipped each case is standard automotive engine oil, which eliminated the lead sticking.

Wayne

[texasmac]

Wayne, I read this in the last link you posted and for the love of me, I don't understand it ...

http://www.kenlightmfg.com/cartridgecaseannealer.htm

The author writes temperature as factor of time except the 750 to 800 for seconds. But on the flip side he says 600 for an hour but the case will be ruined.

So guess I'll have to continue with the old fashioned way: bare handed with a flame spreader propane torch - spin the case with the thumb & index finger in low light - heating from just above the shoulder for those calibers & the seated bullet depth for straight cases ... up to the mouth. When the area turns a bluish green (625 - 650), the case is laid down on a cotton towel to cool ... not dunked in an ice bucket which does not cause brass metal to be annealed.

All the cases are initially annealed and the cases are only mouth expanded 0.001 to 0.002 for the bullet being used and go back in the same recipe box including the same bullet diameter so they are not work hardened aka FL sizing. For those cases, if there is a distinct decrease in accuracy, then they are annealed again as an indication the mouth is not adhering correctly to the chamber wall

Granted there are Chevy's Chysler's and Ford stated ways to anneal but I can anneal a 100 pieces of brass the old fashioned bare handed way in less than 20 -30 minutes and am satisfied they are properly annealed

John,

I understood those two comments of ken's to mean if "whole or complete" cases are heated to the temps he mentioned. Note he says "head and body included", not just the necks.

Wayne

[303Guy]

I once dried some annealed cases in the kitchen oven set on warm enough. I forgot them and they spent the night in the oven and trust me, they were thoroughly annealed! One could tell by the look - they had lost their brass shine. One of them got into the undamaged brass and the unsupported head expanded quite dramatically in my mini 14. No gas leakage though.

[brassrat]

A guy who teaches reloading at Cabelas told me to anneal into a hot pot of sand.

[montana_charlie]

A guy who teaches reloading at Cabelas told me to anneal into a hot pot of sand.
That is interesting enough to play with a little bit.

[country gent]

Fine sand would be no diffrent than lead or salts used a small stand in the bottom of a pot to maintain deptk into the sand and a casting thermometer shoud make a very reliable set-set-up. One of the small lee dippers with adjustable heat a light sheetmetal stand in like a thimble shape. Sand to cover and set the depth and a casting thermometer to maintain heat. Stick one case in to stand stick second case in and remove first should be enough time if not go to 3 case rotation.

[bigted]

now that makes sense to me ... sand ... I may have to try this ...but... im with the "old fashion" group. I use the propane torch and a socket that helps with the heat sink so my case heads don't get overheated.