Case Annealing - Please edjamacate me...

[Jim_P]

OK. I've been rolling my own for over 20 years. Mainly pistol and 7 MM Rem Mag. What's the reason to anneal the case necks and when is it necessary?

Reason I'm asking is with my new .308, I've noticed the brass I got from Harnady was just brass, but the cases from Lapua are neck annealed (can tell by the discoloration). Should I be annealing all my case necks?

Thanks

[Hickory]

Every third or fourth time is my schedule for annealing.
I have 44 mag brass from 1972 that's been loaded at least 30 times, (light loads) out of a 50 round box, I still have about half.

[country gent]

Anealing brass cases reduces removes hardness and sprinyness from the brass. it helps to keep it from cracking. Some factory brass shows the annealing ( Lapua, sometimes winchester and remington, Lake City and military cases normally have a very distinct color showing), some has had it polished to the point the anneal no longer shows. It is a simple operation to do the big thing is not to anneal the case head at the same time. Most use a tourch to quickly heat the neck shoulder to dull red or better still catch the blue color change and either set aside to air cool or water quench. A deepwell socket of appropriate size to loosly hold the case works good to slowly spin it in the flame of a propane torch. Watching for the color changes. I perfer to water quench as it helps stop heat from getting to case heads.

[GhostHawk]

I recently annealed 10 .303 british cases to fireform into brass .410 shells. I just left the primers in and used my lead pot.

I did give each case a touch of wood butter (Olive Oil, coconut oil and beeswax in roughly equal amounts)

You could see a small black ring in the lead when I pulled the case out. I just locked each one into a pointy nosed small vise grips and did a 20 count, pulled and dumped into water. Didn't lose a single case yet, so something is working right.

Hard part is turning the front of the rim's down a bit until I figured a piece of 2x4 and a drill bit made a good point for the base end to rest on. Brass got chucked into a half inch powered drill. Then I just used a small file and some steel wool after to clean it back up smooth and shiny.

Cheaper than the buck a piece magtech .410 brass besides it gave me something to do for a couple of days.

[Doc Highwall]

Here is a good article on case annealing.

http://www.accurateshooter.com/technical-articles/annealing/

[Bzcraig]

Anealing brass cases reduces removes hardness and sprinyness from the brass. it helps to keep it from cracking. Some factory brass shows the annealing ( Lapua, sometimes winchester and remington, Lake City and military cases normally have a very distinct color showing), some has had it polished to the point the anneal no longer shows. It is a simple operation to do the big thing is not to anneal the case head at the same time. Most use a tourch to quickly heat the neck shoulder to dull red or better still catch the blue color change and either set aside to air cool or water quench. A deepwell socket of appropriate size to loosly hold the case works good to slowly spin it in the flame of a propane torch. Watching for the color changes. I perfer to water quench as it helps stop heat from getting to case heads.

Great post and I anneal exactly the same.

[Der Gebirgsjager]

I use a propane torch and a shallow baking pan. Fill the pan up with water to the desired height and stand the cases upright so that only the part you wish to anneal is above the water. Heat individually to a dull red and tip them over into the water so that each is completely immersed with a small screwdriver.

[1066]

What ever method you use, you could take a lot of the guess work out of it by using the Tempilaq heat indicator paint until you get the feel. Ideally you are wanting your neck and shoulder to quickly heat up to around 750-800F but not let the base get too hot in the process.

If you are looking for absolute accuracy and consistent neck tension then a machine is the way to go, if you are just interested in extending case life or part of a fireforming process then the drill and socket method works well. For consistent timing you could use a smart phone with a metronome app set to one second beats.


Personally I now machine anneal all my long range rifle brass after every firing as part of the normal prepping routine. I believe heating the brass to a dull red is too far.

[Vann]

Just like every other part of reloading there are many different ways to do the job with good results. I've tried heating them in a pan of water, dipping them into a lead pot, slowly turning them with a lee ez trim shell holder in a drill, spinning them with a small drill bit chucked in a drill backwards with the smooth end inserted into the primer pocket , and a few other ways. The one thing that is always consistent is that I always drop them into water after heating them. The way I do it now is I just hold the case by its head in my fingers and slowly rotate it through the blue feather of a propane torch. I try to keep the feather about 1/2" long and watch for a blue line to start working its way down the cases neck, as soon as it extends down just past the shoulder I drop it into cold water. Using this method I can anneal 100 brass in around 5 minutes, with absolutely no chance of overheating the case head. I use this method on everything from 223 Rem to 7MM Ultra mag.

When I first started annealing brass I found that by sitting in an almost dark room while heating the neck I could watch the inside of the neck and quench it as soon as it started to get a very faint glow. It seems that you will see the inside of the case starting to glow before the outside.

As far as how often I anneal, that really depends on the brass. Some brass I anneal after every firing and others can go through 5 or 6 firings.

Just my thoughts,
Vann

[1066]

I've found that using the colour change of the brass to assess correct annealing can be very misleading. If I clean a bunch of cases with stainless steel media and straight away anneal half the batch, I often get virtually no colour change. If I anneal the other half a week later I often get the classic "Lapua" blue look.

Quenching in water only stops you burning your fingers when you pick up a case to admire your handiwork.

[country gent]

When I talked to a tech at starline about the annealing ( Iwas getting a reddish pink anneal line instead of blue an curious why it had changed inthe same basic process being done only change was the batch of brass). He claimed that cartridge brass composition and or impurities in the flame carborizing or oxidizeing lean or rich also had a affect on color change. When I do them in the lead pot full of clean glass making silica sand there is no color changes at 850* and a small soak time of 15 secs or so. But the spring back in the case mouth /necks is gone and soft. There are many ways to anneal from the simple torch and quench method top lead pots with molten or hot materials to dip cases into to machines that are timed rotation thru torch to give very consistent processes. I have been told that ammo case manufacturers use induction heaters in line to anneal cases. Like any heating / welding operation keeping impurities and oxegon out of the mix saves alot of hassles. The induction heater seems like an interesting way to go no flames. electric induction nothing hot untill case is passed between uprights. We used them to expand bearing races to install on shafts. Didnt take long to get a bearing hot enough to expand enogh to slide on and when cooled was back to a press fit. I could see an induction heater in line right after the stamping press and the cases running thru it as the press runs.

[Jim_P]

Induction heating looks like a good possibility. I just may need to gove this a try. Looks simple enough: http://www.rmcybernetics.com/projects/DIY_Devices/diy-induction-heater.htm

Maybe with some belt fed (i.e. a narrow fan belt turning at a fixed speed moving the cases through the induction loop) to do this.

Whoo hoo. A project....

[str8wal]

I just hold the case by its head in my fingers and slowly rotate it through the blue feather of a propane torch.

I do this as well, but I drop the case when my finger and thumb tell me it is getting hot.

[Mauser48]

When you drop the cases in the water doesn't it just re harden them? I'm know this is the case for other metals but not sure about brass. Also how many loading a can you get out of let's say a 30-06 if annealed properly. The load being like an m2 ball load.

[Vann]

No, when brass is dropped into water it stays soft.

As far as how many times you can reload brass. I had a batch of 50 308. brass that I loaded 20 times according to my records before I tossed it due to loose primer pockets and a signs of case head separation. These were medium power cast loads not full power jacketed loads.

[Jim_P]

This thread got me thinking (Dangerous!!!). Many of the current annealers out there use propane torches to heat the brass. But the electronic inductions idea peaked my curiosity. So, I gave eBay the old seach-a-roo and found a 1000W induction power supply for $45.00 out of China (Hey, where'd you get your PID?). OK, now that may work for the heater portion and may need to build a 24 or so volt power supply to drive this board. No problem (I have an electronic hobby background and am an Amateur Extra [Ham] radio operator).

So. how to drive the case through the induction 'furnace' so to speak.

I was thinking two small toothed belts. About 1/2 inch wide. One turned inside out and every other tooth or so clipped off and then glued to the other one. May have to cut it to make it fit, but that won't be a problem. With a motor driving a cogged wheel it would be the forward movement. With the second inside out and clipped making a gap big enough for a case base, it would move the cases forward. We'll call this belt the 'Forwarder'.

Another motor/cog/belt on the side at 90 degrees to the forwarder belt, running faster than the forwarder belt to spin the cases while passing through the induction coil. Put a strip of nylon or teflon on the other side and with a couple of thumbscrews and springs to make it hold the cases to the spinning belt to adjust for calibers. The coils would need to move up and down to adjust for case height, but that's a couple of more thumbscrews. Might not need this at all if I design an inverted "U" shaped coil. Gotta play with this idea!

Both motors would be on speed controls. This way you can adjust heat time and spin rate.

Might be the new PID sort of home made solution. Only doing induction annealing!!!

Most of the motors and belts are available as surplus and I know of at least two places where they are cheap. People use them for robotics and stuff. Saw motors at one for $9 each!

I'm thinking for about a hundred bucks this just might work! Imagine an automatic induction annealer for $100 bucks. Set it on the edge of the table with a bucket or tray of water under it and all you need to do is feed cases on the belt. They come out after annealing and drop into the bucket/tray.

Gotta get to ordering and then to work. If this does work out, I will certainly post here for others to see/build/enjoy.

[smoked turkey]

I have used the exact method as posted by Vann for a few years with perfectly good results. I was getting cracks in the necks of expensive 416 Rigby brass due to work hardening of the brass so I had to do something. Since I've been anealing as described I have had no more problems with cracked necks!

[dragon813gt]

Induction heaters have been discussed before and become cost prohibitive quickly. You'll need one w/ an almost constant duty cycle.

[Norbrat]

I recently set up my spare 10lb Lee pot to melt potassium nitrate salt as per http://castboolits.gunloads.com/showthread.php?153620-Annealing-Setup post #20

I used a thermometer, held the temp @ 900° and found 10 seconds worked well for the 308 cases I was annealing. I used an Ove glove, did one case at a time and watched a second counter to get the 10 seconds, then dropped the case into a bucket of water.

[1066]

Here's my homemade machine in operation - just simple gas fired.

https://www.youtube.com/watch?v=Jv75-9p9yFA

Induction annealing may be the future but I think it will be a year or two yet before all the bugs are shaken out. Even then, it may be quicker than a gas burner, but will it to be simpler, cheaper, more reliable or more consistent.

This is the best induction annealer set-up I've seen, just needs a decent case feeder.

https://www.youtube.com/watch?v=EGfGV8xrfak