Annealing with Hard numbers

[swampratt]

Well so much topic on annealing I decided to kill some once fired Lapua 308 cases.

I did a test to end some if's, but's and or's .

Ok so talk of what temp or what color to make a case.
I shot 2 308 Lapua cases over 40 times each with no annealing and bullet seating forces were really close from start to finish. NO Annealing.

That can't be said of all brands of cases.

Now for the test I Just did.

1X fired Lapua cases necks brushed with nylon brush then Lube with Hornady wax inside and out. Then FLS .. Then remove Lube with towel and Q tips and then brush again with nylon brush.. Chamfer with VLD a very pronounced chamfer ,Very deep to eliminate the "what if" the case mouth was hanging on the metal.

So then I cleaned the necks again with Q tips.

Now insert 178 Amax and check seating pressures.

What!!!!!
OH yes Case # 1 is not annealed.
Case # 2 was annealed for the regular 8 seconds.
Case # 3 was annealed for 16 seconds..This produced a glowing red neck with the lights off in the room.

Case #4 was annealed with lights on and glowing red neck was observed.
This took 24 seconds.

Bernzomatic Propane torch was used.

Yes I seated them deeper than need be.. this is a Test!. No powder


#1 Not annealed 75 PSI to seat bullet
#2 8 seconds 78 PSI to seat bullet.
#3 16 seconds 72 PSI to seat bullet.
#4 24 seconds 50 PSI to seat bullet.

I used the sharpie so you can see the heat path. Regular Sharpie BTW.

 

[Calamity Jake]

Did you re size/expand the neck after annealing? and before the seating test?
Brass moves a little with high heat. I think that's what happened with #2,
it contracted when the heat first hit it but the heat wasn't applied long enough
to cause some amount of expansion as it took more pressure to seat the bullet.
Correct me if I'm wrong.

 

[swampratt]

I annealed the cases..And then I resized them.

All Neck ID measured the same .306"
After firing you loose a small amount of spring back as the case hardens..Some Brass Alloy mixes will show this more than others.
72 or 75 or 78 psi in a group of cases to me is perfectly acceptable..You get that 50 psi out of there as that will show up as the flier.

Then look at it like this..you shoot 100 yards you may see it as a smallish flier 1/2" away from the others maybe a lot more.
Now shoot that same deal at 300 yards.. could be 3" out of the group ..

The farther you shoot the more difference seating pressures will make.
In my mind 10% or less would be fine between seating forces.

Now I also took a fresh not touched Virgin Lapua 308 case and seated a bullet in it.
The neck was not chamfered.. the inside of the neck was NOT brushed ,, I left the rough Virgin surface.

As the bullet tried to get past the case mouth the gauge spiked to 60psi then the bullet went in abruptly and pressure dropped to 45 then spiked back up and down like chattering.. Not good in my book..If i brushed the neck and sized it things would be different..And they were as I did just that on another virgin case.

Nice even pressure climb to 72 PSI as the bullet seated.. as the bullets are scooting through the cases the pressure remains constant.
Those up and down spikes need to be eliminated.

Annealed cases will have more spring back and exhibit more holding forces on the bullet.
I used to think softer meant less tension.. but it is not soft vs hard as much as it is springback.

And again alloy makeup plays a role.. I do not think all manufactures have the same alloy. Fact I know they do not.

http://chemistry.about.com/od/alloys/a/Brass-Alloys.htm

 

[Calamity Jake]

Ok You've played with annealing a lot more than I have. I also don't have any kind if a force gage to use while seating,
I just have to go by feel.
I anneal every eight to ten firings or sooner if I find a split neck in the lot.

 

[DRC458]

Interesting. Thanks. I've never timed when annealing. I just go for that soft red glow with no lighting. Now, I'll have to anneal a variety of cases and time how long it takes me to get there!

BTW - Do you quench your cases after annealing and, if so, with what?

 

[swampratt]

I used to do the cases stood up in a pan of water anneal and tip over.. then I went to dropping them into a bucket of water.

I then read much information and found you do not need water.. I just began annealing by holding the cases in my finger tips and turning them in the flame.

If it gets too hot to hold you went too long.
I can anneal a .308 to the correct temp Using 750f Tempilaq drop it onto the formica counter top and pick it up quickly with my fingers at the case head and it is not hot yet, Will be in 1.5 more seconds though.. but it cools quite quickly in the air.

I hate waiting for my cases to dry..In fact i have pulled the cases from the Pin Tumbler and shook the water from cases and towel dried the outsides off and started annealing with the case being a little wet inside.

I do mine with lights on and spin them..Cases are very shiny and clean and this aids in seeing changes in brass color.

Soon as it hits the flame ,,one thousand 1, one thousand 2, one thousand 3, etc. etc.

I used to count like that staring at the second hand of the clock when i was young and had to sit in the corner.
I got really good and could time a minute within a couple seconds.

Worked for timing yourself under water holding your breath..Count to yourself though..Not outloud!!
I could stay under for 2.5 minutes when i spent lot's of time in the water during summer days.
Had friends time it...Swam under water and got a white farm duck by the feet once in the old pond behind plaza towers.
That duck did not like people much..Really did not like me. That was around 1977

 

[gfercaks33]

I think I need to finish learning the basics before I get into this, but in my search what annealing is I found this.

Enjoy
http://68forums.com/forums/showthre...oject-Complete!-Plans-and-parts-list-included!

 

[swampratt]

Love that annealer. Thanks so much for the link.

 

[Calamity Jake]

I like the tipping over in the water method myself, I don't want any heat on the head of the case.
I use an old record turntable with a cutdown #3 coffee can setting on it turning at 45 RPM.
I have a 5/8" ID flat washer centered and super glued to the bottom of the can, stand a case
inside washer half covered with water, in low light heat neck shoulder area with propane torch
to a count of 8-10 then tip over in water and do it again.
One of them fancy annealers would be nice!!!

 

[swampratt]

You ever catch a .308 case from semi auto.
That case head gets smokin hot. At least the ones i picked up from a setme my friend was shooting