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gareth96
04-03-2019, 01:13 PM
Powder coating at 400F for 20 mins, 124gr 9mm boolits, lead is mostly COWW. All other factors being equal, how much does water quenching after casting increase hardness as compared to quenching after powder coating? Is one better than the other, does the re-heating during the PC process reduce any of the after casting quenching hardness gains, do one of the two, both? Etc..

Walks
04-03-2019, 01:55 PM
I don't water quench PC, not enough experience.

But I water quench every bullet I cast, DAD's way so I do it that way too. Except for MuzzleLoaders and cap & ball.

Doing that way since I can remember. Late 1950's.

I don't think water quenching twice would achieve anything. But I really don't know. Have to try some and do a hardness test.

osteodoc08
04-03-2019, 02:04 PM
You’re essentially water quenching when you dump your PC in water. Essentially using the oven heat quench method.

My recent WQ COWW+1% tin was a BHN 22 after 1 week. Originally the ACWW I tossed over to cool normally were an 11-12 BHN. This is using a Saeco lead hardness tester.

klenke.ryan
04-04-2019, 12:55 AM
Here's a really good video on the subject.

https://youtu.be/2fbjs-lErL0

Sent from my XT1650 using Tapatalk

bmortell
04-04-2019, 01:07 AM
good to know I can get approx 20 hardness by water dropping after pc cook, I have air cooled and sized ones, im gonna re bake 20 of them and water drop so I can try harder ones for accuracy comparison.

gareth96
04-04-2019, 07:32 AM
Here's a really good video on the subject.

https://youtu.be/2fbjs-lErL0

Sent from my XT1650 using Tapatalk

Awesome, just what I wanted to know!

Sig556r
04-04-2019, 07:42 AM
Quenching before PC tumbling may also contaminate the surface of CBs due to quality of water, container or rag wipes that may affect adherence of PC.

RED BEAR
04-04-2019, 08:00 AM
I do quench after casting for all rifle bullets and some magnum hand gun bullets. Others i want dead soft any hand gun in the 600 to 800 fps range.

cwlongshot
04-04-2019, 08:36 AM
I have never seen such changes with water quenching... YES they get a harder reading no doubt. But never ever anything close to twice as hard!!

I ran a test last night with a bullet I was PCing to see what the baking has done. I never trusted testing after PC as the PC itself would give false readings.

A friend suggested I not coat one bullet but run it thru the 20/400 PC bake and re test. I did nto re test last night, as it was getting late for me. But I will test it tonight. The bullet was a perfect 15 on my LBT tester.

Generally speaking I air cool my cast, but always quench my PC.

CW

waksupi
04-04-2019, 11:05 AM
Something I experimented with a few years ago.

By changing the temperature of your toaster oven in around 20 degree increments can give you a specific hardness range for bullets.
Once you make a chart of the temperatures and hardnesses after quenching, you have a good reference sheet for the future.

marek313
04-04-2019, 11:27 AM
I dont remember when or where and it might have been here but someone did test this and what the author found was that if you PC your bullets you dont need to water drop when casting instead just water drop after you PC. Basically water quenching when casting is a waste since your heating that bullet back up so just water quench after you PC. Thats what I've been doing because this way I dont have to wait for my bullets to cool and I get to use less lino and tin when mixing my alloy. For the most part I only add some tin to my range scrap and I only add lino to magnum and rifle alloy.

Taterhead
04-04-2019, 12:08 PM
I PC, then size, then heat treat and quench.

My theoretical knowledge might be off, but it seems like raising the bullets to 400F for PC would at least partially undo any benefit provided from quenching from the mold.

Conditor22
04-04-2019, 01:23 PM
https://i.imgur.com/MI10JVy.png

fredj338
04-04-2019, 02:51 PM
I quench after coating out of the oven. Using my CabinTree, I see about a 3-4bhn improvement with range scrap, ymmv.

fredj338
04-04-2019, 02:54 PM
good to know I can get approx 20 hardness by water dropping after pc cook, I have air cooled and sized ones, im gonna re bake 20 of them and water drop so I can try harder ones for accuracy comparison.

I doubt you get that, closer to 15-16bhn? My range scrap goes 9-10. Water dropping out of the oven after 15m @ 400 in ice water yields about 11-12bhn a couple days later.

reddog81
04-04-2019, 04:02 PM
I doubt you get that, closer to 15-16bhn? My range scrap goes 9-10. Water dropping out of the oven after 15m @ 400 in ice water yields about 11-12bhn a couple days later.

That seems much more realistic. It also depends on how long you wait to measure. I've never done much testing of hardness, but I've always read that the hardness of water quenched bullets will be the highest right after you drop them into the cold water. Testing a couple of days later and they'll be noticeably softer and waiting a couple of weeks longer results in even softer bullets. I usually wait weeks, months, or years before shooting anything I cast so any benefit of water dropping will be long gone.

gareth96
04-04-2019, 05:53 PM
This all begs another question.. Does powder coating a boolit slow the reduction in hardness over time? Since you're essentially vacuum sealing it...

RED BEAR
04-04-2019, 08:07 PM
Using wheel weights and dropping in ice water i get a bhn of 25 to 26. That pretty much doubles the air cooled ones.

bmortell
04-04-2019, 11:00 PM
I just baked ww pc boolits 400 20min, air cooled one, cold water dropped the other, put them both in room temp water after to make sure temp is same. I put a drop of grease on the nose to reduce friction then lined them perfectly nose to nose in a hydraulic press.
239239 sientifical testing confirms one is harder

AR-Bossman
04-04-2019, 11:36 PM
How does the lower PC'ing temps like 275 effect hardness if at all? Any idea what temp will start any hardening? Seems 400 is the magic number. I seen a chart all the way to 480 and the hardness climbed with each step up.