Annealing machines

[doghunter]

Bulk Annealing

G'day.

My method is crude and simple, but it works quite well.

I heat a tray of sand (1" deep) to 400°C (just over 750°F) over a gas (portable BBQ) burner.

The cartridge cases are suspended by their base (extractor groove) between two slotted plates that slide together to hold them and slide apart to drop them.

Jam neck first into the hot sand, count to ten and voila!

My aluminium plates hold twenty (.223) cases at a time. Temperature is measured with a thermocouple attached to my multimeter.

Wear gloves.

* doghunter *

 

[jffshooter09]

G'day.

My method is crude and simple, but it works quite well.

I heat a tray of sand (1" deep) to 400°C (just over 750°F) over a gas (portable BBQ) burner.

The cartridge cases are suspended by their base (extractor groove) between two slotted plates that slide together to hold them and slide apart to drop them.

Jam neck first into the hot sand, count to ten and voila!

My aluminium plates hold twenty (.223) cases at a time. Temperature is measured with a thermocouple attached to my multimeter.

Wear gloves.

* doghunter *

Hmmm interesting....how long does it take to get the sand to temp and how hard is it to maintain the temp once its there?

 

[doghunter]

Bulk Annealing In Heated Sand

Hmmm interesting....how long does it take to get the sand to temp and how hard is it to maintain the temp once its there?

G'day.

My sand container is a heavy cast aluminium circular tray. I use dry fine sand, it does not stick to the cases, but I run them through an ultrasonic cleaner with 10% citric acid to be certain.

It takes 20 minutes for the temperature to stabilise then I turn the burner off as the sand holds the heat for about 5 minutes (this is sufficient to do 100 cases). If I had to do more it is just a matter of re-lighting the burner.

I did contemplate using salt, but sand was cheaper and it worked very well from the start.

The annealed necks and shoulders are very consistent with the annealed band evenly distributed around the case body.

The results are far superior to my attempts using a propane burner in the traditional way as I found it difficult to get even and repeatable heating around the necks.

I did look at the multiple burner annealing machines and decided to try something less sophisticated.

It's also a quite inexpensive method, thermocouple probes are readily available to suit digital multimeters. I checked the calibration on mine by dipping into molten lead.

I was actually surprised that nobody else came up with this. I live in the Australian bush so a bloke has to make do with what's available.

Regards * doghunter *

ps. I actually do hunt wild (feral) dogs - they are a real problem where I live - they kill sheep and native animals

 

[jffshooter09]

G'day.

My sand container is a heavy cast aluminium circular tray. I use dry fine sand, it does not stick to the cases, but I run them through an ultrasonic cleaner with 10% citric acid to be certain.

It takes 20 minutes for the temperature to stabilise then I turn the burner off as the sand holds the heat for about 5 minutes (this is sufficient to do 100 cases). If I had to do more it is just a matter of re-lighting the burner.

I did contemplate using salt, but sand was cheaper and it worked very well from the start.

The annealed necks and shoulders are very consistent with the annealed band evenly distributed around the case body.

The results are far superior to my attempts using a propane burner in the traditional way as I found it difficult to get even and repeatable heating around the necks.

I did look at the multiple burner annealing machines and decided to try something less sophisticated.

It's also a quite inexpensive method, thermocouple probes are readily available to suit digital multimeters. I checked the calibration on mine by dipping into molten lead.

I was actually surprised that nobody else came up with this. I live in the Australian bush so a bloke has to make do with what's available.

Regards * doghunter *

ps. I actually do hunt wild (feral) dogs - they are a real problem where I live - they kill sheep and native animals

I really like this idea, a member ran a thread on predator masters forum on how to build a machine at home that looked like a simple effective way to to go and I was going to try something similar . I've been using the ol socket /torch method for a long time with ok results but always wonder just how uniform they are from start to finish. But I also have to question how consistent even a machine can be, flame temp and time can always very a bit from batch to batch. It's seems as long as you can maintain a constant sand temp with this method it would be a fairly economical and effective way to go. If possible I would like to see some pics of this set up, especially the case holders.