Annealing: Harbor Freight propane torch 3 burner + hose

[Marco Califo]

Annealing: Harbor Freight propane torch 3 burner + hose
https://www.harborfreight.com/propane-torch-with-three-burners-91899.html

This product includes three noozles, or burner heads, (round, flat and one that wraps around copper pipe). That burner head fits 1" copper pipe. It is "U" shaped and has holes in the inside of the U.
I think this sounds perfect for annealing. Heat the shoulders of each casing in the U to desired degree.
Use the Zoom feature and enlarge the middle burner

The inside surface is perforated porous foil.


Full setup: Setup cases on a plywood turntable. Two round pieces, one drilled with 1/2" holes around the out side, spinning on a center bolt. Cut a 1" notch in the lower one for the annealed cases to drop through. Position and stabilize the burner over the notch just off from the radii of the notch axis (at 1:00 o'clock).
Heat the case by turning the turntable so that the case enters the U, heat, turn a little more and it drops through into a bucket.

I will be shocked if nobody has thought of this and tried it.

 

[jpx2rk]

Sounds like a good plan, let us know how it works.

 

[hounddawg]

good luck, I have over 20 reloads on some old .308 Palma brass that I used the drill, socket and torch routine on. It was probably over/under annealed but still shot sub MOA at long range and never had any sort of case failure

 

[Unclenick]

That wrap-around burner is unusual, so you may be the first on the board to try this.

The reason for that burner design is speed. Propane torches are notoriously slow at sweating copper and most plumbers use air-acetylene torches, acetylene combustion producing more BTUs per second and therefore heating the pipes faster. I've never had a wrap-around torch, but I have a double inward-directed nozzle oxy-acetylene torch and it heats copper for silver soldering about four times faster than a single tip the same size by supplying not only twice the BTUs but also cutting off the heat escape path from the opposite side. So expect your heat times to be short and accidental overheating that weakens the brass to be easy to do by mistake.

 

[FrankenMauser]

I've seen it done - just not with that particular burner.

I've seen multi-torch machines, induction element machines, and even a guy using two heat guns with the same concept.
Most people use a single flame for simplicity and ease of tuning.

jmorris should be along soon to show his machine...

 

[hounddawg]

when I first acquired my Annealeze I tried a "turbo" tip with propane and found it very difficult to control the amount of heat and went back to the normal plumbers torch. Good luck with the project but I suspect it will be hard to control the heat. Just for what it is worth I stopped annealing a year and a half ago and with no brass failures and the precision/accuracy has not suffered in the least

 

[mikld]

Good idea. Reminds me of an induction type heater. I didn't see it anywhere but is the single tip, not the flat or wrap around tip, a "Turbo" flame or "pin point" flame?

 

[Marco Califo]

UncleNick, What is the good temp window? I have Templaq for 700 degrees, and was planning on 1/2 second after that activates. If the window is 750 to 1100, that range should be easy. At what temp does the brass weaken?

 

[LE-28]

I think somewhere around 450F + is where annealing begins.

 

[hounddawg]

somewhere between 797 - 1380 F according to MATWEB

http://www.matweb.com/search/datasheet_print.aspx?matguid=b01f631374b74445876819dd6ed86467

the temp is also highly dependent on time and the composition of the brass.I wouldn't sweat it too much.

I have some 10 year old Lapua Palma with the SRP brass that was annealed using the dark room and drill method. When I first started really getting into precision reloading I was convinced I had probably over annealed the heck out of those necks but I never split a neck and they shoot great. Primer pockets were giving out after 20 or so loadings. I still have at least 70 of them in my drawer though. Turns out that getting the tip of the neck dull red did not harm them in the least as far as shootability. Unless you go past the shoulder too far it is hard to screw it up

edit - some specifics at this link, these tests were on 70/30 cartridge brass

https://vacaero.com/information-res...rmation-and-annealing-of-cartridge-brass.html

Annealing experiments were conducted on a number of the cold worked specimens. Figures 5a and b show color etched images of the specimens cold reduced 50% and then annealed 30 minutes at 500 and 700°F. No difference in the microstructure is seen in the specimen held 30 minutes at 500°F while a very small amount of recrystallization is observed in the specimen held 30 minutes at 700°F. Figures 6a and b show color images of 50% cold reduced specimens held for 4 and 8 minutes at 800°F while Figures 6c and d show 50% cold reduced specimens held 15 and 30 minutes at 800°F. No change is observed after 4 minutes at 800°F, while a minor amount of recrystallization has occurred after 8 minutes. Holding specimens for 15 and 30 minutes at 800°F revealed partial recrystallization after 15 minutes and full recrystallization after 30 minutes. The grain structure is relatively fine but is not uniform in its distribution.

Figures 7a and b illustrate the grain structure in color after 15 and 30 minutes at 900°F. The 15 minute hold produced a non-uniform grain structure while the 60 minute hold produced better results although the grain size distribution appears to be duplex. Figures 8a and b show a B&W and a color image (Klemm’s I reagent) after annealing 30 minutes at 1300°F which produced a fully recrystallized, uniform grain size distribution but coarse grained (as in Figs. 1 and 3a). Figures 8c and d show the same specimen but color tint etched using Klemm’s III and Beraha’s PbS tint etchants. Both are excellent for use with cartridge brass.

 

[Marco Califo]

Good info. Thanks HD.

 

[hounddawg]

For those seeking the perfect anneal there is little doubt the AMP will realign the crystal structure, my question is does ductility affect shooting or brass life enough to justify the cost. I stopped annealing altogether last year when the wheels on my Anealeeze needed replacement and have seen no changes

 

[Marco Califo]

Annealing is also useful for cartridge conversion. I have a lot of LC 7.62 that I want to convert to 7mm-08. I tried that without annealing, and now, I will try anything else. So I will buy that torch tomorrow if in stock locally.

I tend to agree with you about the perceived "need-to-anneal". I only look at doing so when something is not working. And I am using LC 7.62.

LC 5.56 I have never thought about it annealing, nor trimming for that matter.

 

[hounddawg]

considering the mental aspect of shooting, if you feel that anneal makes a difference then you need to anneal. If you get on the line and are worried about your ammo/gun/environment etc you have already lost. First few times I shot without annealing I was a worried puppy and was convinced I would have flyer after flyer. It took me a month or two to get comfortable shooting non annealed brass. Just my 2 cents worth

oh and yeah it definitely will make the brass more ductile and easier to do case reforming

 

[RC20]

The reason for that burner design is speed. Propane torches are notoriously slow at sweating copper and most plumbers use air-acetylene torches, acetylene combustion producing more BTUs per second and therefore heating the pipes faster.

Lo many years having done that. MAP gas worked good up to 1.5 inches.

After than, you needed the acetylene setup and 3 to 4 inches were buggers.

Last job they were still taking out 3 and 4 inch copper joints where the clown did not heat it right and over 20 years leaks through the only bit of solder holding on the far side.

 

[RC20]

Houndog:

I got tired of split necks. Havn't had any since I went with the Annie.

You will see them show at 6-8 rounds unless you are over annealed.

That said, I over annealed my first batches and they shot pretty good.

Not sure what the break point is, I am after 1/2 MOA and I can feel the cases get snarky (hard) for bullet insertion unless I do.

 

[RC20]

HD:

I think you should add a caveat to the so called Anneal Temps as they are misleading.

Annealing is to temper the metal for ductility.

Once you have gone over the edge it may change grain structure but if it does not return a hardened condition, its gone too far and is no long an anneal and you are tempering metal. You want spring back.

800 would be the short term max (under a second I believe) for ammunition brass.

I think that should be added as well as the caveat if you see any color of orange into red its overdone.

Fatal? No. But its over done and gone past anneal and will never need treatment again.

 

[hounddawg]

@RC if you ever need to temper the brass here is how it is done

https://www.highettmetal.com.au/blog/brass/how-to-temper-brass

To temper brass, you will need to place the object in and oven or kiln and set the temperature to 565 degrees Celsius (so, you’re general home oven certainly won’t get hot enough). You will need to leave the object in the oven or kiln for at least 2 hours.

565C = 1049F

I used the torch/drill dull red method for a few years and in excess of 15 - 20 reloads on some Lapua Palma SRP brass I never had a case failure and shot many a .25 and .3 MOA group at 100. I might spin the .308 barrel back on my model 12 this winter and shoot some of that old Lapua Palma and see how it puts em on paper in some FTR matches just for grins

 

[Marco Califo]

RC, I would like to understand and be able to believe: please post factual reference material to SPECIFY WHAT THIS IS and support your statement:

Once you have gone over the edge ... 800 would be the short term max (under a second I believe) for ammunition brass.

 

[RC20]

Marco: There are a lot of annealing threads on this and I am not going to dig them all up.

Factually, once brass is properly e annealed, it will have spring to it and it will also work harden again (which means you need to anneal again)

In my case I can achieve 800 degrees in a very short time period so that is where I am (induction)

A torch takes longer.

If you keep it at 800 degrees for more than a second, it goes into soft. Soft will never again work harden, nor will it have spring back

Its not an unsafe case as long as you don't temper it down to the base.

So 800 is your operating area for short term heat, longer term if you can keep the case base cool, you can anneal at 500 using more time (its very hard to do)

HD clearly over annealed and has soft necked brass so it will not split.

Anything over 800 degrees past a couple of seconds (brass has to warm up) you no longer are annealing, you have made soft brass.

With the high temps he is talking about you will get the base soft and that will have disastrous consequences. The base needs to stay hard.