Salt Bath Annealed Necks collapse during seating

[JimSC]

About 5 seconds at 1000 F is too long? If so, how is 3300 F for 3 or 4 seconds better? If you have any data to support that, I'd be very interested in reading. Inquiring minds would like to know.

Getting brass to 3300F would be a trick since yellow brass melts at about 1700 F. Just for grins I took an old Starline .260 Rem case and did the drill and torch routine til the neck glowed orange, sized it , seated it, pulled and and repeated that half a dozen time and the shoulders never collapsed and the brass always sprang back when the bullet was pulled

Of course by the time I got it that hot I had a rainbow halfway down the case body and the case was ruined. The case body got annealed too far down for safe firing so I crushed the neck with pliers and trashed it

Just checked and zirconium is the only metal that would not melt at 3000 F

 

[mikecr]

1,000degF dip will not fully anneal cartridge brass. But as mentioned, we don't ever need or want to fully anneal.

To get the full thickness of brass at desired annealing temp with a torch usually means heating it's surface hotter than middle & inner. And 5 seconds of torch application at 2500+ would fully anneal and burn off some zinc. So the brass has to be spun under flame to prevent that.

 

[JimSC]

1,000degF dip will not fully anneal cartridge brass. But as mentioned, we don't ever need or want to fully anneal.

To get the full thickness of brass at desired annealing temp with a torch usually means heating it's surface hotter than middle & inner. And 5 seconds of torch application at 2500+ would fully anneal and burn off some zinc. So the brass has to be spun under flame to prevent that.

Brass has almost the same melting temp as zinc does. If the zinc goes away so does the brass. Melting points are 1,650 to 1,720 F for brass and 1650 for zinc. Do you guys know how brass is made

https://www.scientificamerican.com/article/to-make-brass-and-alloys/

 

[mikecr]

I agree with you. And in my view it's not a good thing to apply temperatures so high to our brass.
It's why I dip anneal. Nothing less than a total idiot screws it up.

 

[JimSC]

I agree with you. And in my view it's not a good thing to apply temperatures so high to our brass.
It's why I dip anneal. Nothing less than a total idiot screws it up.

annealing is not just temperature it is temperature applied over time.The hotter the metal gets the less time. However it is just a old wives tale about the zinc gassing off or the brass getting too soft. Most the records that were set between mid 90's to the last two to three years were set using brass that had been by heating them until the necks glowed dull red. That would be be around 975F or higher depending on the person doing the annealing. Pretty sure I took mine well above that. Be hard to argue that all those record scores over the years were shot using ruined brass

 

[Webster]

Brass has almost the same melting temp as zinc does. If the zinc goes away so does the brass. Melting points are 1,650 to 1,720 F for brass and 1650 for zinc. Do you guys know how brass is made

https://www.scientificamerican.com/article/to-make-brass-and-alloys/

Zn melts ar 787F.

 

[JimSC]

Zn melts ar 787F.

you are right, I messed up when I converted from K to F . Good catch, thanks

Still the point is that to become brass the zinc is melted with with copper at a much higher temperature than zincs own melting point

 

[Texas10]

Brass has almost the same melting temp as zinc does. If the zinc goes away so does the brass. Melting points are 1,650 to 1,720 F for brass and 1650 for zinc. Do you guys know how brass is made

https://www.scientificamerican.com/article/to-make-brass-and-alloys/

Everything I ever wanted to know about how brass was made Pre-Civil War...

 

[jthor]

JimSC is right. Zinc just doesn’t gas off brass at high temps. Brass has to be chemically attacked for dezincification to occur. However, high temps will accelerate the chemical attack, which is pretty typical of chemical reactions.

 

[JimSC]

lot's of false beliefs regarding this subject. Fifty years ago pre internet I can understand

Everything I ever wanted to know about how brass was made Pre-Civil War...

I was just trying to point out that once the two metals have formed a alloy (brass) the zinc does not vaporize. Lots of old wives tales regarding this subject floating around the community