Annealed (?) case question

[seanb]

I just ran a batch of .338 Lapua mag brass (made by Lapua) through my ultrasonic cleaner, dried them off and hit them with compressed air and then threw them in my little bread oven. Unfortunately I stupidly forgot to check the temp it was set at (250 F) and when I took them out some had these, I'm assuming, annealed spots on them from where they contacted the metal pan. Do you think they are safe to shoot or should they be trashed?

 

[aloreman]

Re: Annealed (?) case question

dont put brass in the oven

 

[DocB]

Re: Annealed (?) case question

Polish in a tumbler and shoot them. Don't put brass in the oven, that's what your wife's hair dryer is for.

HTH,
DocB

 

[milo 2.0]

Re: Annealed (?) case question

They will be fine, tumble them, it will disappear.
Mark them, shoot em, and keep an eye on them. 250deg wont hurt brass.

 

[Triggerhappy]

Re: Annealed (?) case question

If it only got to 250 degrees it is probably okay. Like stated before DO NOT anneal in the oven. I use a propane torch, just anneal the neck/shoulder.

 

[seanb]

Re: Annealed (?) case question

OK thanks guys. I wasn't trying to anneal them, it just happened. I was just drying to make sure they were dry as I wanted to load them back up right away.

 

[bas402]

Re: Annealed (?) case question

Well I'm not going to agree that you should use. You should never get within an inch of the case head over 200 degrees as it will weaken the brass to much and case possible case head seperation. I anneal each cycle on all my brass on a Bench Source annealer and check my cases with Tempilaq. I sure wouldn't think about it on a .338LM case. Call David at bench Source, he knows his stuff. Your choice though

 

[turbo54]

Re: Annealed (?) case question

At temperatures considerably lower than the "transfer" temperature, annealing happens slowly.

Brass DOES anneal at 250°F, but slowly.

Hiw long were they at 250? 20 minutes is fine. An hour+ is questionable.

Try scratching the casehead of the one that looks the worst with a screwdriver, and get a feel for what it takes. Then repeat on a case that you didn't bake. If you can't tell the difference, forget about it. If you can tell, toss them.

Come up with a better drying method, such as a drying box.

 

[Tripwire]

Re: Annealed (?) case question

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: seanb</div><div class="ubbcode-body">OK thanks guys. I wasn't trying to anneal them, it just happened. I was just drying to make sure they were dry as I wanted to load them back up right away. </div></div>

Did you learn anything?

Like instant gratification is not always worth it?

One step forward and three steps back, mebbe?

338LM is expensive brass to just fuck around with.......

I doubt you really hurt them that badly, but the question is, is the structural integrity of your face worth the risk.

I water quench when annealing for the exact reason you stumbled on here......I don't want ANY heat getting to the case head and the water quench is my insurance policy it won't happen.

 

[Tripwire]

Re: Annealed (?) case question

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: turbo54</div><div class="ubbcode-body">At temperatures considerably lower than the "transfer" temperature, annealing happens slowly.

</div></div>

FWIW, brass will anneal at room temperature....albeit much slower than any of us would have patience, or a lifetime, to wait for.

That's your reloading geek trivia for the night...........

 

[Gene Poole]

Re: Annealed (?) case question

You're probably fine. That's just some chemical discoloration. What did you use in the ultrasonic? Probably not citric acid.

Use citric acid and detergent in your ultrasonic. Rinse with distilled (or at least "softened" water) and let then air dry. Use Isopropanol if you want them to dry quicker. Only use an oven if it's an industrial convection oven with a lot of air flow (and still use a clean rinse to avoid water spots).

 

[High Binder]

Re: Annealed (?) case question

This seems like a weekly post around here and as an engineer with metallurgy classes under my belt I've posted about this exact topic countless times yet the misinformation persists. So without typing out my usual novel, here's the skinny: this type of brass will anneal at 250 but it takes DAYS. The color change you see is OXIDATION and is 100% harmless. You can dry in an oven with no problems and if you want to minimize the oxidation give your brass a quick rinse in water with a little baking soda mixed in before it hits the drying stage. That being said, drying in an oven is painfully slow, I use the alcohol method.

 

[Tripwire]

Re: Annealed (?) case question

My question is why the hell is drying brass RIGHT NOW so damn important anyway.

Can't people plan their time any better than that?

Turn the damn things upside down in a loading block, turns the lights out, get a beer, crack it, and do the old lady.....MUCH more rewarding.

Load the brass tomorrow.........

 

[X-fan]

Re: Annealed (?) case question


Feeling lucky?
How good is that little 10 cent thermostat in your made in Taiwan oven?

I would not use those cases. Why risk it?
You can tell they were in for way too long and if the case heads hit 400 degrees the case head will fail.
So will your rifle.

 

[High Binder]

Re: Annealed (?) case question

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: X-fan</div><div class="ubbcode-body">
I would not use those cases. Why risk it?

You can tell they were in for way too long and if the case heads hit 400 degrees the case head will fail.
So will your rifle.
</div></div>



As spelled out above: The discoloration is oxidation and is perfectly safe.

You're only partly right on the 400 degree statement but you missed the other critical component of annealing which is time. See annealing is as much about temp as it is time at whatever temp. It takes hours at 400 degrees to anneal brass.

 

[dstewart51]

Re: Annealed (?) case question

You could always put them aside, use them for "fouling loads" with a lighter powder charge (-10% your full power loads).

I set aside brass they I mess up on one way or another, like over trimmed, bumped back a bit too much or what ever. I keep pulled bullets for this purpose as well.

Like others, I don't believe 250deg would totally kill the brass. If you have to question it dont use them for full power loads.

 

[Gene Poole]

Re: Annealed (?) case question

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: High Binder</div><div class="ubbcode-body">This seems like a weekly post around here and as an engineer with metallurgy classes under my belt I've posted about this exact topic countless times yet the misinformation persists. So without typing out my usual novel, here's the skinny: this type of brass will anneal at 250 but it takes DAYS. The color change you see is OXIDATION and is 100% harmless. You can dry in an oven with no problems and if you want to minimize the oxidation give your brass a quick rinse in water with a little baking soda mixed in before it hits the drying stage. That being said, drying in an oven is painfully slow, I use the alcohol method. </div></div>

I'll defer to your metallurgy knowledge (I'm a chemist and I only had one metallurgy class) but I disagree with you on the baking soda. It is slightly caustic and will cause more discoloration--especially if dried in an oven--than leaving a bit (what remains after rinsing) of acidic residue on the cases. Best to rinse with distilled (or clean "soft") water. I've found citric acid to be the best at cleaning away oxidation and leaving no discoloration.

 

[turbo54]

Re: Annealed (?) case question

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Tripwire</div><div class="ubbcode-body">My question is why the hell is drying brass RIGHT NOW so damn important anyway.

Can't people plan their time any better than that?

Turn the damn things upside down in a loading block, turns the lights out, get a beer, crack it, and do the old lady.....MUCH more rewarding.

Load the brass tomorrow......... </div></div>

There are a million legitimate reasons to get brass dry sooner than later.

It isn't unreasonable for a person to want brass dry more quickly than natural drying.

Many folks aren't cool with individually handling each piece of brass - for example loading each one neck down in a loading block.

For a few $$, you can make a drying box with an incandescent lightbulb (while the feds will still allow us to buy them), and a muffin fan.

My brass is bone-dry in 45 minutes...which is plenty of time to have a beer and bang the old lady...

 

[High Binder]

Re: Annealed (?) case question

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Gene Poole</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: High Binder</div><div class="ubbcode-body">This seems like a weekly post around here and as an engineer with metallurgy classes under my belt I've posted about this exact topic countless times yet the misinformation persists. So without typing out my usual novel, here's the skinny: this type of brass will anneal at 250 but it takes DAYS. The color change you see is OXIDATION and is 100% harmless. You can dry in an oven with no problems and if you want to minimize the oxidation give your brass a quick rinse in water with a little baking soda mixed in before it hits the drying stage. That being said, drying in an oven is painfully slow, I use the alcohol method. </div></div>

I'll defer to your metallurgy knowledge (I'm a chemist and I only had one metallurgy class) but I disagree with you on the baking soda. It is slightly caustic and will cause more discoloration--especially if dried in an oven--than leaving a bit (what remains after rinsing) of acidic residue on the cases. Best to rinse with distilled (or clean "soft") water. I've found citric acid to be the best at cleaning away oxidation and leaving no discoloration.
</div></div>

Here's where that info comes from:

http://www.6mmbr.com/ultrasonic.html

<span style="color: #3333FF">"The Mad Chemist Needs A Neutralizing Agent
At this point the brass was coming out with no carbon deposits whatsoever, but I wasn’t happy with the darkening of the brass so I figured a neutralization step was needed after the vinegar to stop the acid’s reaction. A water rinse was fine with the acidic BC case cleaner, but not sufficient with vinegar. Baking soda (BS) seemed like the easiest and most readily available option to neutralize the reaction. The BS was simply dissolved in water in the proportion shown below. I went through nearly a dozen runs to come up with the best combination of vinegar, dish soap and baking soda."</span>

I work in a lab too but I do oil (petroleum industry) related work so I'd have to defer to your knowledge here. Perhaps the baking soda is only needed when a strong acid is used and not needed when only using water/dish soap? Thoughts?

 

[seanb]

Re: Annealed (?) case question

The reason was that I had just shot these brass, get home, my brother calls and says he wants to go shooting tomorrow, so I wanted to get these brass cleaned up and reloaded ASAP. I had other stuff to do besides wait hours and hours (if not a day or more) for the brass to fully air dry.

Thanks for all the responses everyone.

 

[Tripwire]

Re: Annealed (?) case question

Here's a pictogram of a faster way, for the impatient souls, that is positively sure to not risk any heat damage from an oven......

<span style="font-size: 26pt"><span style="font-weight: bold">+</span></span>

<span style="font-size: 26pt"><span style="font-weight: bold">+</span></span>

<span style="font-size: 26pt"><span style="font-weight: bold">+</span></span>

<span style="font-size: 26pt"><span style="font-weight: bold">+</span></span>

<span style="font-size: 26pt"><span style="font-weight: bold">=</span></span>

 

[High Binder]

Re: Annealed (?) case question

^^^LOL