Metalworking: Annealing brass?

My 30-30 brass, having been reloaded a few times, is getting work
hardened. I'd like to extend the useful life of the cases if possible.
I've read a lot about annealing brass, some of it quite contradictory.
So yesterday, I took what I think I understand of that and gave it a
try. I chucked up the shell holder from my Lee trimming tool in a
portable drill and fired up a propane torch.
As I understand it, I'm looking for a gold color change at the neck
(indicating 700 to 800 degrees?) , but without losing the shine from
the rest of the case - as an indication that the case neck has been
annealed but not the rest of the case.
When the color change happened, I dropped the case in a bowl of water to
stop the heat from continuing down the case and head. (Brass doesn't
"heat treat" like steel in that respect)
Spinning the brass seemed to give an equal treatment all the way
around (which should avoid hard spots in the neck area) , but judging
by color change alone I wonder about the consistency from one case to
the next.
I haven't seen an IR thermometer that goes high enough to monitor the
process.
Keep the case head below 300 degrees (F)
The critical temperature is 482 degrees at which the first changes in
grain structure can occur.
Annealing brass to "dead soft" will ruin the case.
It will be dangerous to attempt to shoot shoot cases.
Anybody have more info/helpful tips/ etc?
(Karl???)
BTW, I'm reloading mostly cast lead these days, and pushing those pretty
hard (trying to stay right at 2000 fps). That seems to work well and
give good accuracy.
Reply to
Richard
Loading thread data ...
Don't they recommend to stand the cases in water anymore, to keep the head-end from overheating?
Your best bet for recognizing temperature is Tempilaq, according to the handloading experts I used to read when I was interested in wildcats. I've never used it but I used Tempilsticks all the time when I was doing more metalworking, and they're great.
Reply to
Ed Huntress
Unless you are full length resizing the case all you need to do is anneal the necks. The usual technique was, as Ed mentioned, to stand the cases in a pan of water - reaching say half way up the case - and heat the necks. when you get a color change then tip the case over. The temperature really isn't that critical as all you are doing is annealing the work hardening that you are doing when you expand and crimp the neck.
If you are using lead bullets you are probably expanding the necks and crimping fairly aggressively so you probably will be annealing more often then a bloke shooting jacketed bullets.
It might be useful to measure the cases and trim to length and possibly ream the necks, if necessarily, occasionally.
Reply to
John B.
Thanks guys.
Yes, lever guns (headspace off of the flange!) tend to stretch the cases over max length in only 3 or 4 rounds. So yes, full length sizing and trimming to length (and yes, expanding (GENTLY!) the necks for lead).
My latest effort is to start resizing so as to headspace off of the shoulder. All that involves is setup for the full length sizer so that the sizer matches a case fired in this rifle. That OUGHT to reduce the amount of growth considerably.
Hadn't heard of "Tempilaq", but I'll go find some.
As for the pan of water device, I have built one that turns Lazy Susan style, but I still need to build a DC speed control circuit to get the speed under control. It takes a good six seconds for the neck to come up to temp and they aren't staying in the flame long enough right now. But even then it's too easy to get TOO hot TOO long and go dead soft.
I want to have a way to cross check the temp - at least until I have enough confidence in what I'm doing!
I asked Santa Clause for an M1 Carbine for Christmas... 30 carbine is a cheap reload with few of the problems associated with 100 year old designs... :)
Reply to
Richard
It's used by small shops for heat-treating, but I think that Brownells and other gun-supply places also stock it -- probably at a premium price.
You can get away with a lot of corner-cutting heat treatment if you have some Tempilaq or Tempilsticks. I used them to determine temperature of the workpieces in a "furnace" made of loosely-assembled firebricks with two big portable propane torches for heat, and got pretty consistent results heat-treating small pieces of steel.
Reply to
Ed Huntress
Let's clear up some terminology. Annealing of cartridge brass occurs in the 800-1400 deg range. This fully softens the brass and is only something you should think about if you're wildcatting.
What you want is called stress relief. This occurs in the 500-650 range. If you are using a turbo torch, stop. These heat too fast and are too oxidizing a flame.
Use a pencil flame torch, you want a soft reducing flame and you may have to cover an air hole to get it. Heat slowly and dance the flame around. As they heat, the necks will darken. Eventually, you will see the darkening disappear as you play the torch across it and reappear as the flame leaves, This is the temp you want.
You don't need to quench, but it is not harmful. On something as long as a 30-30 you would have to screw up big time to get the head up to any critical temperature.
The shoulder should be fine in the same temp range but will probably never get there.
The inaccuracies of torch heating and exposed surface area will leave you with the crimp area softer than the rest of the neck, which is exactly what you want.
You should not have to do this too often. It depends on your load and crimp.
Paul K. Dickman
Reply to
Paul K. Dickman
That explains a lot. I was trying to apply this technique to a different piece of brass. Once I put it in the water bath I could not get the color change on the exposed section: The water bath acted like a heat sink big time. I was using a propylene-air torch.
Michael Koblic, Campbell River, BC
Reply to
mkoblic
Thank you, sir. That's a keeper.
Richard the cavelamb
Reply to
Richard
Don't know if it is the same brand, but go to
formatting link
and put either "heat stick" or 604 in the search box and you will see their selection of crayons ($11.48 ea) and liquid paint, in melting temps from 104F to 2000F. I'd assume msc
formatting link
and probably
formatting link
also carry them, if you prefer them over mcmaster carr.
----- Regards, Carl Ijames
Thanks guys.
Yes, lever guns (headspace off of the flange!) tend to stretch the cases over max length in only 3 or 4 rounds. So yes, full length sizing and trimming to length (and yes, expanding (GENTLY!) the necks for lead).
My latest effort is to start resizing so as to headspace off of the shoulder. All that involves is setup for the full length sizer so that the sizer matches a case fired in this rifle. That OUGHT to reduce the amount of growth considerably.
Hadn't heard of "Tempilaq", but I'll go find some.
As for the pan of water device, I have built one that turns Lazy Susan style, but I still need to build a DC speed control circuit to get the speed under control. It takes a good six seconds for the neck to come up to temp and they aren't staying in the flame long enough right now. But even then it's too easy to get TOO hot TOO long and go dead soft.
I want to have a way to cross check the temp - at least until I have enough confidence in what I'm doing!
I asked Santa Clause for an M1 Carbine for Christmas... 30 carbine is a cheap reload with few of the problems associated with 100 year old designs... :)
Reply to
Carl Ijames
snip---
Probably a good idea so long as they're being fired in the same weapon.
I had a 218 Bee as a young lad. Damned thing stretched the brass so much it would separate at the head after a few reloadings. I should have tried just neck sizing, but that never entered my mind. You know how kids are.
Harold
Reply to
Harold & Susan Vordos
Go to the second hand store and buy a nice big cake pan deep enough to stand your brass up in with the neck and some shoulder above water ...fill pan until proper depth reached.
Hit the neck and shoulders with your propane torch on low..until the brass glows a dull orange. With the tip of your torch..knock the brass over into the water. Repeat as necessary. Very simple
Been doing it this way for at least 30 yrs. Which bullet do you get the best results with?
I shoot either a 130gr GC M1 Carbine design, or a 150 gr Lovern style in Marlin Microgroove or a bore rider in everything else
Id have to go into the shop and get the mold numbers.
Gunner
"There are no leftists in mainstream American politics.
Just two right wing parties, one hard right and one softer." Christopher A. Lee, 8/18/2013
Reply to
Gunner Asch
Dead soft in the 3030 NECK and shoulder ......will harm nothing and will prolong brass life many many times. I average 30 reloads from regularly annealed (about every 10th firing) and neck sizing only
Ive got brass in the cases that have been reloaded at least 50 times
Gunner
"There are no leftists in mainstream American politics.
Just two right wing parties, one hard right and one softer." Christopher A. Lee, 8/18/2013
Reply to
Gunner Asch
e: >My 30-30 brass, having been reloaded a few times, is getting work >hard ened. I'd like to extend the useful life of the cases if possible. > >I've read a lot about annealing brass, some of it quite contradictory. > >So yes terday, I took what I think I understand of that and gave it a >try. I chuc ked up the shell holder from my Lee trimming tool in a >portable drill and fired up a propane torch. > >As I understand it, I'm looking for a gold col or change at the neck >(indicating 700 to 800 degrees?) , but without losin g the shine from >the rest of the case - as an indication that the case nec k has been >annealed but not the rest of the case. > >When the color change happened, I dropped the case in a bowl of water to >stop the heat from con tinuing down the case and head. (Brass doesn't >"heat treat" like steel in that respect) > >Spinning the brass seemed to give an equal treatment all t he way >around (which should avoid hard spots in the neck area) , but judgi ng >by color change alone I wonder about the consistency from one case to > the next. > >I haven't seen an IR thermometer that goes high enough to moni tor the >process. > >Keep the case head below 300 degrees (F) > >The critic al temperature is 482 degrees at which the first changes in >grain structur e can occur. > >Annealing brass to "dead soft" will ruin the case. >It will be dangerous to attempt to shoot shoot cases. > >Anybody have more info/he lpful tips/ etc? > >(Karl???) > > >BTW, I'm reloading mostly cast lead thes e days, and pushing those pretty >hard (trying to stay right at 2000 fps). That seems to work well and >give good accuracy. > Go to the second hand st ore and buy a nice big cake pan deep enough to stand your brass up in with the neck and some shoulder above water ...fill pan until proper depth reach ed. Hit the neck and shoulders with your propane torch on low..until the br ass glows a dull orange. With the tip of your torch..knock the brass over i nto the water. Repeat as necessary. Very simple Been doing it this way for at least 30 yrs. Which bullet do you get the best results with? I shoot eit her a 130gr GC M1 Carbine design, or a 150 gr Lovern style in Marlin Microg roove or a bore rider in everything else Id have to go into the shop and ge t the mold numbers. Gunner "There are no leftists in mainstream American po litics. Just two right wing parties, one hard right and one softer." Christ opher A. Lee, 8/18/2013
If it "glows" at all, the brass is ruined, you want just a bit of change in the oxidation colors. A torch is NOT the way to do this if you want tempe rature control, a lead bath and a good thermometer is the way to do it. Ma ke a fork for the heads and do 4-5 at once. Immerse to the shoulder, remov e and dump into water. Keep water and lead separate! This also works for tempering springs.
Stan
Reply to
stans4
Sounds "entertaining"...
Reply to
Richard
Not at all. Been doing it for years
Another way to anneal brass..is to get your lead melting pot up to temp..and quickly dip your case necks into the molten lead..then drop it into a bucket of water. You Will get a fine wash of lead on a few cases..but it will largely wipe off.
"There are no leftists in mainstream American politics.
Just two right wing parties, one hard right and one softer." Christopher A. Lee, 8/18/2013
Reply to
Gunner Asch
Its called "taking care of ones tools"
"There are no leftists in mainstream American politics.
Just two right wing parties, one hard right and one softer." Christopher A. Lee, 8/18/2013
Reply to
Gunner Asch
I found out a bit about that. The "crayons" are actually rather chalky. Hard to mark on polished brass. The suggestion was to do the marking and heating before polishing.
The paints are probably easier to use.
A dab of 450 on the case to make sure it doesn't overtemp.
And a dab of 700 on the neck to make sure it gets hot enough.
From:
It is critical to understand that we are talking about annealing case necks only. The rest of the case is work hardened during manufacturing and left that way on purpose. It must be strong enough to contain the pressures of firing, and annealing any part of the case except the neck is potentially dangerous. Do not do it.
Under no circumstances should you let the case body get anywhere near 700 degrees. If you do, the case is ruined, and should be crushed and discarded.
You cannot anneal brass in an oven! You will ruin it.
You must use another method, like a torch or possibly some sort of inductive heater that applies the heat locally to the neck area only.
Some have suggested dipping case necks in molten lead (which melts very near 700 degrees depending on the alloy). This works in theory, but in practice, it's not such a hot idea. Spattering, sticky lead, and the fact that lead is a dangerous poison make this not such a good idea.
Torches are by far the most commonly used heat sources for annealing. They're cheap, relatively easy to use, and do the job well.
Reply to
Richard
Richard fired this volley in news:r4idnW1- EYeV9ITPnZ2dnUVZ snipped-for-privacy@earthlink.com:
PIFFLE! Do you never cast bullets? IF you're concerned with breathing lead fumes, wear a mask.
But anyway... lead doesn't melt close _enough_ to 700F to properly do the job. Even Super Hard doesn't melt much above about 650F.
As far as "sticky" ???? You've never heard of smoking a piece; right?
Lloyd
Lloyd
Reply to
Lloyd E. Sponenburgh
I don't reload, but it occurs to me that one of those heat guns intended for stripping paint and the like could work, and won't be so likely to overheat things. Many are advertised as being adjustable in the 500 to 700 F range.
Put cases in a shallow pan of water, heat the necks, tip the cases over into the water.
Joe Gwinn
Reply to
Joe Gwinn
I guess he felt it necessary to pass along the warning.
As for smoking a piece, I dunno, Lloyd. If I did I don't remember it! :)
Reply to
Richard

PolyTech Forum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.