DIY Electrical Annealing Of Rifle Cases

I've been finding MOSFET switched timing modules and switches lately for dirt cheap...
Not that the average guy knows what this means, here is the rub...

Relays have mechanical contacts, no matter how low the current you run through them, the contacts opening and closing will eventually give up,
Or the mechanical parts, hinges, springs, ect. will fail...

MOSFET is solid state switching, no moving parts at all,
A fancy 'Transistor' that handles lower currents with these little units,
And I let the circuit board mounted MOSFET trigger a cheap, run of the mill relay, easy to find, easy to replace, about $1 in bulk when I need to switch higher currents...

The MOSFET trips the relay, the relay delivers the higher current to this or that...
It's an added step, but since the timers and other stuff is built into that little circuit board, the longer you can keep it living, the better off you are in the long run.
A bad higher power relay is easy to diagnose and replace, so it's a little more wiring in the front end, but it saves you a TON of aggravation over time!
These little surplus timer/switching circuit boards MIGHT NOT be so cheap and easily available when the unit decides to fail, so whatever you can do to keep them alive is a good idea...
At $3 to $7 each, it's not a bad idea to pick up your replacement parts now while they are cheap & available!

There is usually room in your DIY case for you to tape the extras in there somewhere, the bottom of my larger project boxes are always full of replacements, fuses, timers, relays, ect. since nothing fails until you NEED it, this puts me back up and running right away instead of trying to hunt down a replacement years down the road when you can't quite remember what the specifics where or where you got it from!

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Something else you might want to consider,
When you are working with 12 or 24 volts DC,
It's perfectly acceptable to use AUTOMOTIVE FUSES, and other automotive components to work out your project...

Keeps the cost down, gives you an INSTANT source for relays, fuses, switches, ect., just as close as the nearest discount auto supply store!
 
I am not sure I understand how the case is kept from being over-annealed, or softened all the way down instead of just at the neck area where we normally anneal work hardened cases.

Jim
 
Here is a 'YouTube' video of one of these little 1,000 Watt induction units in action against a screwdriver, using a low dollar power supply and induction unit... About $65 or $70 worth of common hardware...

https://www.youtube.com/watch?v=1wwlbN-9jsU

Why everyone wants to anneal their screwdrivers is beyond me, I pay too much for my quality tools to heat them to the point of uselessness.
Must have a 'Lifetime' warranty...

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The idea of case neck annealing is two fold...

1. Remove any stress, hardening in the case shoulder/neck so the case shoulder/neck doesn't separate or crack.
This would be a big issue for the guys wanting to get the longest life out of the cases.

2. To return the case necks to 'Dead Soft' for proper re-sizing,
And for proper bullet 'Hold' (Retention) in the case neck.
Consistency in bullet retention from case to case.

A 'Hard' neck won't conform to the bullet as well as a 'Dead Soft' case neck will,
Same as soft metal jaws on a vice will hold any particular work piece better than hard jaws that have just a few contact points will.

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Not that anyone seems to care much,
A PRECISE heat control, in this case, how much TIME the case is exposed to the working coil,
AND,
How much energy that coil is imparting directly to the brass,
Will determine how 'Soft' the case will get.

As for just keeping the 'Heat' in the neck/shoulder of the case,
In my experience, you simply drop the bottom of the case out of the coil,
The coil is most effective in CLOSE proximity, with the heated material CENTERED in the coil.

Just an inch away/outside the coil, the effects of the coil are MUCH lower.

You simply have the coil high up on the case, so the neck/shoulder get the most energy induction, while the lower sides/head receive virtually no intense heat from the coil interaction.

Dropping the case into water to instantly stop the heat transfer from neck to base is perfectly acceptable.
Brass doesn't 'Quench' like steel does, air, water oil, doesn't matter, the brass will not harden once heated no matter how it's cooled.

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While 'High' (High Quality) Brass is mostly considered to be 60/40 Copper/Zinc,
There are trace elements in the brass, very small amounts of this or that,
These trace elements give the RIFLE brass it's particular qualities.

Lead, Antimony, Selenium, Ect.
It's VERY EASY to cook these elements to the point of separation from the base material,
Or even cook those trace elements out of the brass entirely.

A common mistake is to flame anneal the brass with temperature sensitive paint on the INSIDE of the case neck, watching for that paint to change color.
This usually results in the Zinc cooking to the surface of the brass, giving it a 'Silver' look on the OUTSIDE of the case.

The factory engineers call this 'Tinning' (probably because a silver color when soldering with 'Tin' solder, this was a desirable color to see),
'Tinning' isn't what you want to see in rifle brass, it means you have raised the Zinc out of the copper base material, and the two are no longer 'Alloyed' together like they should be.

The reason is the flame on the OUTSIDE of the case is making the outside MUCH HOTTER than the inside, The case is working like a heat shield against the flame annealing,
And by the time you get a color change INSIDE, the outside is WAY OVER HEATED, and the alloy is separating.

Induction solves that issue, since it excites all the molecules at the same time, giving you even heating throughout the case material.
When the paint changes color (and you can paint outside or inside), you are getting an accurate reading of the case temp.

The coil isn't heating up,
It's INDUCING (Induction) the molecular structure of the case to heat up,
You aren't applying ultra high temp to one side of the case, waiting for the heat to migrate through the material to the inside,
The material of the case is heating itself through resistance/induction.

Hard concept to grasp, but once you get it, it makes good sense for this application.
 
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The 'Tech Geek' or engineer version of this is,
You are looking for a Rockwell B scale of 70 or less,
You are looking for a Rockwell F scale of 97 or less (if I remember right)...

Metal workers call 'Hardness' by 'Dead Soft', '1/4 Soft', '1/2 Soft', ect.
It's an industry term used by workers that don't regularly do Rockwell testing to have an exact hardness to work with.

Cartridge casing brass comes in on big rolls,
The rolls are set aside until labs and hardness testing are done,
Labs to determine EXACTLY what's in the material constituting 'Brass',
And hardness testing to make sure the brass arrives 'Soft' enough to be worked by the machines with minimal wear.

The brass is punched into round 'Cups' that are pretty thick, then annealed.

Those 'Dead Soft' cups are inserted into a HUGE lubricated press die,
And a 'Pin' applies enough pressure to make the brass 'Plastic' and push it up the sides of the pin.
This produces a rough shape of a cartridge.

More press & forming machines continue to form the brass into cases.

Some brass are annealed up to 5 times, while others only see annealing two or three times, depending on if it's a straight wall case or bottle neck case.

Bottle neck cases MUST be annealed at least twice during the forming of the necks, usually more like 3 or 4 times.

*IF* the cases are overheated during the annealing process,
They will NOT pass labs at the back end of the process, when batches have QC test pulls go to the lab.

Some companies sell their mistakes directly back to the brass manufacturer to have the brass smelted, re-formulated, and made into new brass sheets/rolls.

Others sell their mistakes to 'Scrappers' that package the brass into 'Bulk' packages and sell it for more than 'Scrap' price....
(Ever wonder why that 'Discount' brass didn't quite work/live like the name brand stuff did?)

When you anneal your own brass, it's a good idea to NOT overheat and separate out the alloy components, this takes pretty precise heat control.
I've posted the videos of the industrial induction annealing processes above, so you know how they do it,
Conveyor that controls the TIME the cases 'See' the effects of the annealing coils,
Cases are allowed to air cool as they continue down the conveyor on the way to further forming, trimming, and eventually QC & loading.

Reproducing the precise induction process isn't seriously difficult,
You can still screw it up ROYALLY,
But it gives you a much more precise and complete annealing than the average flame annealing processes do.
This gives you a better chance at a PRECISELY done product, and a more uniform/repeatable case on which to base your loads.
 
Been using 2 torches now for 5 plus years, Never an issue yet. I did destroy a few cases when I first started, but that's how you learn. 2 torches, cordless drill and a bucket of ice water. Get about 6 cases a minute. Are they perfect?. The line tells me they are, Am I doing it correct or long enough. Getting 16 to 20 reloads out of my 308 cases ( still not neck splits but figure that's enough). Got about 400-6MMBR cases going on load 28 already, no neck splits yet. I did decide to build a Annealer now though, just because it looks so much faster and easier. But it will be the torch set up again.
 
I'm a 'DIY' junkie!
Love building my 'Rube Goldburg' gadgets.
I do go the long way around the barn sometimes, but I usually don't try to reinvent the wheel,
I'f I can't make something that is faster, more efficient, or does a consistantly better job, I usually don't fool with it...

I also don't get shocked while trying to change flashlight batteries,
So working with electrical projects doesn't scare the crap out of me...

I've got the parts coming in to build a half dozen of the annealers for guys that want to try electrical annealing, I'll take pictures this time and see if the moderators will let me post them.

Right now, I have 'Rifle Case Processing Machine, Version 2.0' bolted to the milling machine table.
The first version had some 'Kinks', mostly mistakes on my part,
This version *Should* kick out bottle necked rifle brass that is much closer to exact SAAMI specification than anything else on the market.

Its just darn hard to build a self powered progressive machine that beats an old 'Rock Chucker' with an iron frame.
It takes a REALLY stout pin press with die plate and table that will NOT flex under the pressure we are talking about.

Went to 2" die pins this time, considerably more expensive, but they *Should* have about 3x the strength it takes to punch the case back into shape without flexing...
I know why the commercial machines cost so much, just a TON of little parts that all have to work in exact time with the press!
A real PITA to get everything working together and make it 'Idiot Proof'...

Doing the feed a little different this time, small primer & large primer both on the same rail, inline.
No messing with trying to calibrate the case size/primer size/primer discard.
Basic small primer .223 size cases on the first 8 stations, then large primer .308 size cases on the second 8 stations.
Easier to add a second case feeder than to refit/adjust everything every time you want to change case size/primer size...
 
Just out of curiosity, and keep in mind I analyze everything,
Why would someone post up they will continue to use a gas torch on a thread about 'DIY' electrical annealing?

Honestly, I'm curious about the reasoning for the posts saying they won't change from gas annealing when its clearly in the title the thread is about 'DIY' and electrical annealing?
 
Could be because they have not the foggiest Idea how to build what you are talking about:o They have gotten set in their ways :)and are to old and dumb to learn something new:(. But I am just guessing:D
Got to have pity on us old farts ya know.
 
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I'm a cranky old fart, but I still try to learn something new every day.
(could be the OCD, I MUST know how everything works!)

Anyway, the timers and induction units are in the country (China, go figure) so it won't be too much longer before I put some more of these together, I'll post some pictures as they go together.

Much easier to wait until several want one and order/build all at once than to have one going together on the bench all the time, in the way...
 
This is the base Induction Unit, around $35-$40 off eBay or Amazon,

And yes, I own the pictures...

IMG_02351_zpsrrsncvs5.jpg


They come with TIGHT coils, and you usually don't want the coils touching.
Touching creates contacts, reducing the electrical resistance, among other things you don't want happening.

IMG_0240_zpsapwn2gqv.jpg


Stick something between coils on both sides, separate them a little bit.
I use a small pocket knife blade, but about anything will work...

The result is a small air gap between coils. You don't have to worry about electrical arcing, it's the actual electrical contact between coils you are trying to avoid, so ANY air gap will work.

IMG_0243_zpsmxd8f5el.jpg


I use a 600°C (1,112°F) fiberglass wrap around the coils, in this case, it was 8mm and 2 meters cost $4....

IMG_0244_zpsedcibkzh.jpg


The fiberglass wrap keeps me from accidentally 'Shorting' out the coils when I bump them with something, a case falls over, and it keeps me from getting burned when I contact the coils from sheer clumsy behaviors.

You don't HAVE to wrap the coils, but if you are like me, STUFF HAPPENS!
Better safe than sorry...

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The idea is to keep your brass, or what ever you intend to heat up, CENTERED in the coil...

This is one way I've found that doesn't cost a fortune and is easy to work with...

It's a #8 (1/2"), LONG (8L) TIG welding torch ceramic gas nozzle.
Being ceramic, heat will never kill it, and it's non-magnetic/non-conductive,
Invisible to the coil magnetic or electrical properties, it's a good way to keep your fingers out of the coil, station the brass (or whatever) mostly in the center of the coil.

IMG_02491_zps7nrjqqxj.jpg


For guys working WITHOUT a timer, mount the ceramic tube as a 'Stop', drop in and pull out the brass.

For guys building a 'Drop Through' unit, you will have to grind (ceramic bits & dremel tool) the inside out a little bit to allow .223 brass to fall through it.

From the base plate mount, a wooden dowel rod will hold the tube upright centered in the coil, I caution against using metal screws to hold the dowel rod, they WILL heat up.
A tight hole and some glue works best...

IMG_02521_zpsyrvbt7xq.jpg
 
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For a REALLY BIG coil like this one,
And I were doing one at a time, I might make a metal (steel) insert,
Use a chamber reamer for the neck of the case,

A chamber cut off from an old rifle barrel works exceptionally well for this task, but not everyone has a specific caliber scrap barrel laying around.

This would heat the metal plug (Mass), and transfer heat to the case neck when you dropped one in.
Depending on voltage input, and your timing in removing the case, you could control the temp of that metal plug VERY precisely,
Allowing you to get a very precise heat transfer to the case...

This shows an old military thin barrel chamber stump,
It will need to be cut off at the threaded end until the neck & shoulder are all that remain from the chamber,
But it makes for an easy way to 'Plug' heat/anneal the cases.

image_zpsdugbusms.jpg


Keep in mind that barrel piece will run about 750 degrees F. so you REALLY won't want to touch it!
 
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Me too,
I'm learning that you guys WAY over-think case annealing.....
Click to expand...

Years ago I decided I would get into annealing. I did not invent anything, I did not discover anything. I did decide there were rules and factors. I applied the rules and factors to annealing and then made equipment for annealing. And then one day a member of a reloading forum contacted me and said he has never seen someone that could alienate so may people in a very short period of time; so he wanted to know if I was for real. He came for a visit and stayed 3 days. I put a few projects gather and introduced him to a few of my resource people.

One of the projects covered annealing; I explained the rules and factors. He said he had no interest in annealing and had no infatuation with using one case for the rest of his life. He is the fan of getting three firings out of a case and then start on another case.

And then there was that time at the gun show when an owner of a rifle built by a friend accused him of building a rifle with head space problems. There is no easy way to deal with that situation so he asked the owner to bring the rifle to his shop. They finished their business and the owner of the rifle moved down to where I was. I ask to see the case, after looking at the case I asked him if that was the only case he had for the rifle and was he loading that one case over and over and over and then about that time the builder of the rifle came over and asked to see the case again. It was about that time he suggested the case be taken to a third non-bias person for examination. The shooter took the case to the non-bias fair and objective person for inspection with the understanding he was not to tell the non-bial person who built the rifle or tell him what I said.

First; the non-bias person pulled the case apart and measured the case body of the case, the case body measured .0025” thick;’ it was about that time the fair and objective person asked the owner of the rifle if that was the only case he had for the rifle and he asked him if he was shooting it over and over and over: anyhow the owner of the case got upset but did come back to the builder and said he was not happy with that old man that pulled the case apart with his hands. He said the old man told him .0025” is a good thickness for paper but that is too thin for the case body. I offered to form 200 cases for his rifle for free, he did not thank me and he never showed up at the shop to get the rifle checked.

If the owner of the case was sizing the cases I do not know how the ram was lowered without pulling the case apart.

F. Guffey
 
POWER SUPPLY.

Most of the induction units will tolerate from 12 VDC to about 48 VDC,
I usually run around 24 VDC,
And I usually use a Radio/Communications or 'Robotic Control' power supply since they are 'Soft Start' and can easily be cycled on and off.

The power supplies will run anything from $15 to $100, depending on what you want to spend, and what you are trying to accomplish...

I'm not about to recommend any specific power supply or part number for anything, since this stuff is on the surplus market as soon as I do they will change part numbers, suppliers, specifications, ect.

I will say, if you order a 1,000 Watt induction unit, then it's a very good idea to match that with a 1,000 Watt power supply!

Wiring is simple, AC in to the power supply,
DC from power supply to induction unit.
If it's a switched power supply, then your timer will install between power supply and induction unit,
Or in the power cord to the power supply, the choice is yours.
 
Mr. Guffy, I don't know what your point is.
Doesn't seem relevant to the issue at hand, which is electrical induction annealing...

I was asked for pictures, and that's what I'm delivering.
 
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