Oh yes. The guy that says brass melts before it anneals. Totally vindicated.
If You weren't so ignorant ,you'd possibly know the difference between melting and annealing . Two totally separate circumstances .
Try reading IF that's even possible in your case . Yo Yo
IT most certainly can happen prior to annealing ,NO different too any other metal being annealed . IF one elevates the Temperature high enough material MELTS or liquefies before annealing can occur . Annealing shifts atoms within the metals structure ,allowing grain or lattice restructuring and this can NEVER happen with cartridge brass REGARDLESS OF TEMPERATURE ,as we haven't the TIME to allow it too .
Annealing is a value of Temperature and TIME , they can vary greatly dependent upon materials . The initial idea of annealing is to reduce stresses within the materials in the case of Brass . Fyi : Hold Brass at 482 Deg. F all day all night ,NOTHING happens . Elevate it and extend time and it begins to happen .
Eric Yuan :
Annealing in metallurgy and materials science is a heat treatment that alters the physical and sometimes chemical properties of a material to increase its ductility and reduce its hardness. In annealing, atoms migrate in the crystal lattice and the number of dislocations decreases, leading to the change in ductility and hardness.This process makes it more workable. In scientific terms, annealing is used to bring a metal closer to its equilibrium state.
An answer to someones question on Brass annealing :
I am unaware of any MIL specification for the heat treatment of alloy 270 (C27000, Yellow brass 65Cu-35Zn). ASTM B601 [affil link], "Standard Classification for Temper Designations for Copper and Copper Alloys,Wrought and Cast", specifies resultant properties in a generic fashion but not process details. E.g., H02 indicates cold worked to ? hard, OS035 indicates annealed to an average 0.035 mm grain size.
ASTM B36 [affil link], Standard Specification for Brass Plate, Sheet, Strip, And Rolled Bar, gives tensile strength and hardness values for C26800 (64Cu-36Zn) and C27200 (63Cu-37Zn) in various tempers. The values are nearly identical (except for spring hard) and should serve for C27000.
To specify an annealing, one needs initial material info and an objective. What is the grain size, the amount of prior cold working, the desired grain size and the amount of further cold working to be performed? Are you certain of the need for annealing? It will reduce the yield strength up to 80% dependent upon initial value. Typical annealing temperatures range from 425 to 750 °C. A relatively low temperature anneal, 1 hr at 300 °C, will yield a small grain size (better for polishing), while a higher temperature, 500 °C, may be necessary to achieve a 50% elongation via cold working. A protective atmosphere is recommended for higher temperatures to avoid oxidation. Testing of grain size or hardness for comparison with values from ASTM B36 [affil link] or the references below is recommended.
I didn't find data on annealing C27000 to improve conductivity. From data for copper, I would guesstimate an improvement < 4 relative %, e.g., from 26% to 27% IACS.
For more annealing details and other properties, see ASM Metals Handbook Vol. 2 'Properties and Selection: Nonferrous Alloys and Special-Purpose Materials' [affil linkon Amazon]. Physical properties of C27000 in cold worked (1/8, 1/4, 1/2, hard, extra hard and spring hard) and annealed (of various grain sizes) tempers can also be found on the Copper Development Association site at www.copper.org.
This past weekend, I annealed about 400 cases; 100, 338LM, 100, 308 Win and 200, 223 Rem. In the past, I use to place the cases in a water bath and dim the lighting so I could see the color change. I had a few problems in the past: making sure I got the brass temperature right and keeping them upright in the bath till after annealing when they would be knocked over in the water for quenching. So with this batch I did things a little different I used the temperature liquid that dried green in color, and liquefied at the 750 degree point and I used a bunch of plastic reloading blocks to hold the cases. The blocks had to be weighted down (I used lead bullets) to keep them from floating. The heating worked pretty good but I needed three hands and eyes to watch the change in the paint and watch the flame then to remove the cases from the blocks and lay them flat in the bath. So I put my granddaughter to work helping out; especially since she is the primary user of the 223. The moving of the cases worked good (she used a pair of piers to move them)
The ceases were then tumbled and dried for visual inspection. The cases were smooth, no cracking under 5x magnification, I saw no abnormalities.
I just finished loading all the 338 Lapua and 308 Winchester and am starting on the 223 Remington. There was no problem seating the bullets no necks developed cracks.
On the next warm day, I will shoot some of this and see how they do after firing.
The ceases were then tumbled and dried for visual inspection. The cases were smooth, no cracking under 5x magnification, I saw no abnormalities.
I just finished loading all the 338 Lapua and 308 Winchester and am starting on the 223 Remington. There was no problem seating the bullets no necks developed cracks.
On the next warm day, I will shoot some of this and see how they do after firing.
I set up MY Annealeez a little different from their factory configuration . Bought an angle ball stud mount fully adjustable clamp setup ,drilled a couple of extra holes in the aluminum case . Rerouted the fuel hose and mounted a precision flame torch pointing away from the cartridge case body .
It now aims at the case shoulder and neck ,rather than being a 90 Deg. intersecting flame it's perhaps 42-45 Deg. ,going away from the machine.
Did Three things , kept the case body and wheels cooler ,it also eliminated that funky phony clamp joke it came with . I've done K's of cases without incidents . In the beginning I used Tempilaq 850 Deg. F. down below shoulders and on case bases just above rebated rim 250 Deg. F .
I then recorded times for ALL Rifle cases I reload for ,so as to eliminate Tempilacq altogether . Measured 1144-1216 Deg. F. at neck ,yet by aiming flame away from the body ,bases never melted the 250 Deg. F. solution . So cases drop into aluminum tray without need for water .
As I quick polish those cases afterwords and size necks while bumping shoulder ,that single reworking restores just the right amount of spring back .
I then can shoot #3 reloads before redoing them again . So far Excellent results as I've gotten #28 reloads on M1 Garand 1942-68 original once fired brass ,so far . Something is working right and haven't lost a single case . I'm going to load those 30-06 until I reach #40 reloads and will then sacrifice one case by slitting it and measuring wall thicknesses in various places . I already have one once fired NO loads slit for comparison .
NO restoring Ductility ,Can't truly anneal as Brass requires TIME at Temperature even at elevated temps ,the atoms within the Metal Don't reform lattice groups or grow grain structure . So the BEST any of us can ever do with cartridge brass is simply soften it ,aka restore ductility .
I got beat down so badly by metallurgist for Boeing and LM for saying I was annealing my brass cases ,then they RE EDUCATED ME of proper terminology . Reluctantly a couple would allow the Term " PARTIAL ANNEALING " , then arguments would break out .
So George settled it once and for all , there was ZERO proof ANY lattice or micro grain had occurred on several samples I provided . George even went so far as to publish results ,concluding at 850 Deg. F required 30 Minutes before Grain began changing .
So Ductility is is for ME ,as I've said You all call it what you want but reforming lattice or grown grain structure YOU AIN'T GETTING !.
Just what comes to mind when I read threads like this with everyone arguing over things that don't matter.
Enjoy : Even got colored photos for the illiterate .
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. Tint etchants also reveal details about the presence, or absence, of crystallographic texture. We note that as the cartridge brass is cold reduced greater amounts the grain coloring becomes more monotone, while when the annealing temperature is increased resulting in fully recrystallized grains with increasing size, the coloring becomes more variable with a random distribution of the colors. A random dispersion of a broad range of colors indicates that we have a random crystallographic texture while a narrow color
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. Tint etchants also reveal details about the presence, or absence, of crystallographic texture. We note that as the cartridge brass is cold reduced greater amounts the grain coloring becomes more monotone, while when the annealing temperature is increased resulting in fully recrystallized grains with increasing size, the coloring becomes more variable with a random distribution of the colors. A random dispersion of a broad range of colors indicates that we have a random crystallographic texture while a narrow color
i do anneal after ever firing using a burstfire annealing unit .very happy with it. getting the timing right is the first thing to get right . not that i have a way to check hardness but i do have a way to measure how much poundage is being used to seat the bullet into the brass. it does make a difference
Guys, from my own experience, I can only add that heat treatment of rifle cartridges is needed only so that the cartridge case can be formed in a matrix with good repeatability of geometry.
It’s just that a lot of people get hung up on the heat treatment of gun casings. What is the temperature, what is the best way to do the heat treatment, they buy a lot of expensive equipment and so on.That's another way to put it.
I deal with this with a gas torch and a screwdriver, everything works.
