Annealing and seating pressure.

[20PPC]

A friend if mine and I were talking today and he mentioned after annealing he was getting higher seating pressure than when he doesn't.
He has a 21st Century hydro press and uses it for his SR 30 BR ammo.
He is annealing every time using a Bench source annealer 5.3 Seconds with a .0105 neck wall thickness.
Annealed brass seats somewhere between 50-60 and the brass that isn't annealed is between 35-40 which is where he wants it.
Has anyone ever experienced this difference in annealed brass needing more force to seat a bullet ?

 

[Metal God]

My thinking is that there is a Resistance/friction difference between the two , annealed and fired . It’s unlikely he has more neck tension on a freshly annealed neck than one that is once fired .

My guess , there is something going on with the interior surface of the case necks that is causing the extra friction to cause the extra resistance resulting in the higher seating pressure .

Has he ran as close as he can apples to apples test . Meaning cleaning the cases include the inside necks so the once fired and freshly annealed are identical as far as residue , oxidation etc. on the insides of the necks ?

 

[CharlieNC]

Work hardening can cause significant variability in seating force and depth, and annealing tempers this to restore uniform seating. This is why I started annealing, it works!

 

[20PPC]

He has gone to every extreme to get everything the same, turning the necks 3 times to get them identical, annealing several different time settings, brushing necks etc.

 

[SKWERLZ]

Annealed necks on super clean brass are pretty sticky.
My filthy brass with lots of carbon in the neck has less force required after annealing.

 

[Straightshooter1]

A friend if mine and I were talking today and he mentioned after annealing he was getting higher seating pressure than when he doesn't.
He has a 21st Century hydro press and uses it for his SR 30 BR ammo.
He is annealing every time using a Bench source annealer 5.3 Seconds with a .0105 neck wall thickness.
Annealed brass seats somewhere between 50-60 and the brass that isn't annealed is between 35-40 which is where he wants it.
Has anyone ever experienced this difference in annealed brass needing more force to seat a bullet ?

The annealing process is HOT and it leaves an oxidation film on both the outside and the inside, especially if the brass has any slightest residue from anything else. That oxidation film is rough, which will result in more friction if it's not cleaned or lubed. Running a nylon brush through it before seating can help. This is why I do annealing first (well, after I deprime the cases) and then clean the brass before sizing.

 

[JMayo]

Re-Lube inside necks. Annealer cooks the lube off.

Time is meaningless. Should be in the flame as little time as possible to get to the "just before orange happens" or the heat migrates down the case to far. Imo

 

[KC MO]

A couple of questions for clarity. What are you using to set your inside neck diameter? Ie expander ball/mandrel to expand necks or standard die/neck busing? IF you are NOT using a mandrel or expander ball, one possibility is that the annealed brass has less “spring back”. The annealed brass is staying where your sizing puts it. If that is the case use a larger size neck bushing to reduce seating pressure. If u are using mandrell or expander ball, i got no explanation

 

[Willie]

The "texture" of the carbon after annealing is not the same as carbon in non-annealed brass. That's why we brush necks and many use Dry Imperial for consistent seating.

I used a Bench Source back before the AMP came along. I didn't see where OP mentioned 1 or 2 torches, but it seems 5.3
seconds was a bit too long on necks turned to .0105". Probably not his problem though.

 

[RegionRat]

If your friend wanted the annealed to be at the same seating force as the non-annealed, why didn't he just adjust the neck size to make it so?

He only needs to use a slightly larger expander mandrel to make it what he wants, so what is missing from the discussion? Why did he not make it so?

There are pros and cons to topics like annealing, and I will be the first to say if you are not going to do it right you are better off not doing it at all. That said, once the details are done the goal is to prevent the upward drift trend in the work hardening of the necks and determine if the variation and extreme spread in the neck tension forces give you better performance. If they don't then he should skip it.

 

[1shot]

Annealing cooks off the carbon that was inside the necks. If your buddy isn't shooting coated bullets, have him apply some dry graphite to the insides of the neck. My guess is that the seating pressure will return to where he wants it.

Lloyd

 

[rijndael]

FWIW: I anneal first, then tumble and size. Tumbling after annealing makes a HUGE difference in the resizing feel, it's much easier after tumbling.

 

[20PPC]

The "texture" of the carbon after annealing is not the same as carbon in non-annealed brass. That's why we brush necks and many use Dry Imperial for consistent seating.

I used a Bench Source back before the AMP came along. I didn't see where OP mentioned 1 or 2 torches, but it seems 5.3
seconds was a bit too long on necks turned to .0105". Probably not his problem though.

I have a Annie so my numbers are meaningless, I do know he is using 2 torches.

 

[JEFFPPC]

I know different gas changes the heat but 5.3 seconds sounds like not enough. Is he starting to get a glow in the neck, I doubt it. Never had the carbon inside the necks cook away. Run a nylon brush is the neck one pass after cool down. Clean off outside zinc release with steel wool. Perhaps a larger bushing is the answer, expander in a turned neck is counter productive. Proper annealing should result in lower and more even seating pressure. Tumbling or sonic cleaning counter productive, I have tried both. shiney does not win.

 

[Tesoro]

He has gone to every extreme to get everything the same, turning the necks 3 times to get them identical, annealing several different time settings, brushing necks etc.

I found that the more I messed with thin necks the worse things got.

 

[6BRA]

The "texture" of the carbon after annealing is not the same as carbon in non-annealed brass. That's why we brush necks and many use Dry Imperial for consistent seating.

I used a Bench Source back before the AMP came along. I didn't see where OP mentioned 1 or 2 torches, but it seems 5.3
seconds was a bit too long on necks turned to .0105". Probably not his problem though.

on a dual torch at .0125 neck at 4 seconds you are getting some orange.

 

[sparky123321]

Since I:

1) Deprime
2) Clean in SS pins
3) Anneal
4) Lube with Royal
5) Resize
6) 20-30 minutes in a vibratory cleaner with corncob and a couple drops of polish to remove the lube.

I don't have this problem. No matter your routine, I recommend a little time in a vibratory cleaner with corncob/polish after annealing. Try it. I bet your seating force comes down.