Annealing cases - blowtorch and induction annealing methods

I use tempilaq and a bench source annealer. Would love one of those AMP induction annealers

@oldAG I am going to make a backup copy of that page and try to collate a few things into ‘knowledge base’ post for articles section. Would be good if you (and @Gwion who seems to know what he’s on about) could post some tricks and tips beyond what’s here.

When i started I over annealed a few cases some by accident and some on purpose. To the point of bright orange / Red you could see the grain change a bit. However the temp at the middle and base of the case did not even reach the annealing temp. The cases were fine to use I may not have got the 1/4 MOA accuracy out of them but no splits or sticking either. A few uses later and they are probably getting hard again.

Thanks for that info @sungazer. Very usefull.

Perhaps to get it spot-on it’s difficult. But to get a practical improvement not so hard.

All i know is what I’ve read, so definitely no authority on annealing. Although, I have learned a few things about metal, heat and colour over the last few years through my interest in forging blades.

From experience, it is very difficult to get repeatable results by reading colour changes. Sure, you can tell when it is way too hot but when you are talking an effective window of maybe 50degC to do the job in seconds… good luck with that!

I guess if it is plinking ammo that you just want to last longer: go for it; as long as you don’t over heat the case body, which would be very bad. Worst is probably that it ends up too soft and collapses in your press. On the other hand, if you are annealing for a consistent neck tension in conjunction with neck turning and reaming, to squeeze the utmost precision out of your rounds for the pointy end of target shooting: at best you are just wasting your time unless you do it properly; at worst you are making things worse due to inconsistent properties of the case mouth.

Sooo, I had a crack tonight and annealed about 20 cases. Just used what I call a “Pencil tip” in an LPG torch and a piece of wooden dowel with a hole drilled in the end to hold and rotate the 30-06 cases. I used the table cloth in the pics for a light coloured back ground and a small lamp for light. (not quite as light as normal shed lights) Just rotated for about 9 seconds until the blue colour could be seen. then dumped them on a damp cloth. Obviously not all identical.
I just held the torch handle in a bench vice. (KISS) Once set up took no time at all. Not perfect but I think good enough to extend the life of the cases.

Here is a random sample.

And the torch I used.

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Looks good, you will have to let us know how they go.

I have a LPG torch exactly the same with two or three different tips, but I am having a lot of trouble getting the correct flame from it. It must be very pressure sensitive.

Jet might need cleaning. Should be a blue flame.

@Oldbloke seen this on Facebook and thought that it might interest you. He is selling them at $400 a pop.

https://www.facebook.com/groups/1442388839331951/

You can make one of them yourself if so inclined. Skips case annealer - black Betty. Was designed by a bloke called skip on the shooting Australia forum with input from a heap of other members. There are a number of YouTube vids from skip and others who’ve made them.

They would be great if you need to anneal 100s. But like many other shooters I only need to do perhaps 20 or 40 at a time. In fact to be real probably should just buy new cases. But I like tinkering and don’t like spending. :grinning:

Yeah, for small batches, what you’re doing with a socket in a drill is good enough once you get your timing.

I batch all my brass in lots of 100 and generally a few batches/cals at a time so can be annealing 3-400 cases at a time so an annealer makes it a bit easier.

@TheDude have you built one of these? Or how do you do yours?
We would love to see some pics.

I use a bench source annealer (https://m.youtube.com/watch?v=OaXzARG5Qz0), if I’d not already bought one I would have had a go making one of skips design. From memory I ordered mine only a month or so before he first posted his first design

If I was going to buy an annealer it would be the AMP but at $1600 it is a big investment. Not to mention way over priced for the technology. To build it would be quite cheap. You can get the hot plates for cooking for $50. I have bought a couple of modules of ebay for about the same but need a bigger power supply the timer also is not a costly piece of equipment. Wish the Chinese would get onto making one.

Ok I have bitten the bullet and bought a heap of parts from fleabay to make a DIY annealer out of one of the ZVS 1000 W modules. The parts list is quite extensive if you want to make a good job out of it.

I am looking for ideas for a Tube or tube inside a tube type of thing that one the winding can be wound around and then stay as a former. Then another piece that will hold the case nice and vertical and central in the heating coil.

Any recommendations of material the is not easily breakable and can with stand 500F-750 F.

The idea is to make a trap door type device so they can drop out the bottom when finished.

@sungazer do you have a link to the project/parts, etc.

Here it is. I annealed my first case last night using a 30V 6 A current limited power supply it took about 7 seconds. It was interesting I used the Ferite open induction unit and when switched on it pushes the case out of the path. So a pretty solid way of holding the case in place will have to be used. Waiting on delivery of a 48V 30 A power supply then will experiment with the closed copper coil vs the ferite.

http://forum.accurateshooter.com/threads/induction-brass-annealer-redux.3908353/

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So I have pretty much finished not one unit but two. Main reason for the two was I bought spare parts in case of failures, I got one power supply for free due to what seemed like a lost package and I bought some alternative components in case I didn’t like one or it broke. which was the case in two instances.
So one unit uses a water cooled work coil to induce the power the other uses a ferite which concentrates the flux in the gap.

The Ferrite unit uses less power and is faster and is a bit cheaper to make I think. However the rate of change of the temperature even with 0.01 second control is so quick overheating may be a issue. You often get a slight glow.

The water cooled coil unit accepts a wider range of cases as is and other coils are relatively easy to construct. it is not as efficient and uses a lot more power and is a bit slower but I think you have a bit more temperature control.

The shelf on each unit is adjustable in height and I have some small rulers still to attach to make repeat setups easy. Under the case is a trap door the drops the case into a pan on one unit automatically on the other a press of the momentary switch. this was a case of buying the wrong timer but not really an issue. On the water cooled unit I anneal a 308 case in 4.35 seconds Same for each case at least its consistent if it is need well that’s a wait and see.

Certainly @Cooper and I found for the 223 case which can be done in 1.2 seconds or less annealing was needed to get back the spring in the case neck. On other calibres I am sure it prolongs life of the necks. My question is will it improve accuracy or maintain it on multiple reloads.

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