What frequency of Annealing for best case life and consisitent accuracy?

[Mikecr]

Fingers on the rim for neck to shoulder only. A light glove where I'm doing deep body dip for a major case reform (like for producing an improved wildcat).

 

[Buckskinner]

Considering that a bottle-neck case is annealed for hours (at least twice) at temps exceeding 1000°F we're pretty safe with what we're doing with our propane torches.

Any luck finding source on this info? If not, should be edited so nobody get themselves killed by annealing their bottleneck brass for hours exceeding 1000 deg F...

 

[CaptnC]

Any luck finding source on this info? If not, should be edited so nobody get themselves killed by annealing their bottleneck brass for hours exceeding 1000 deg F...

I think it's pretty obvious he is a very experienced shooter who likes to troll gun/shooting forums.

But yeah...as little as I know about annealing a case it is good to know that he's BS'ing everyone...

 

[Alex Wheeler]

Annealing is not a sure accuracy improving process. Some combos need more neck tension than annealed cases can provide. IF your combo likes lighter neck tension Annealing will probably work for you. If your going to do it, do it the same and every time. But test it both ways to be sure that it actually shrinks your groups. Do not assume it always will.

 

[tim_w]

I know for a fact I do not have the experience of a number of shooters on here and am perfectly happy to be incorrect as thats one way to learn.

With that said,

I am not sure I have experienced the need for more neck tension than a PROPERLY annealed neck can provide in terms of its effect on accuracy that sizing the neck down tighter could provide. Not saying it does not exist just that to me that seems to point to some other issue with the load development or case prep. I have never had to size a neck down so far under the bullet diameter I could not start the seating to get enough tension. Most all the time I am good somewhere between .002-.005 usually I like around .004

Just thinking out loud here but to me if a annealed neck can not provide enough tension it likely was over annealed. Otherwise if it was just annealed to the hardness as it came from the factory then even new it could not provide enough tension and likley even after one firing it would still be too soft as you can size a neck down a good deal before no longer fitting a bullet (not that this would be a good thing over all)

All in all this is likley just splitting hairs

 

[Mikecr]

Tim, tension is not a chosen interference fit, nor a seating friction. It's spring back against seated bullet bearing.
Spring back is affected with annealing(typically lowered), so tension is affected with annealing. Tension affects load timing, so you want your load developed at a given tension that you can manage. Some cartridges favor high neck tension, or jammed seating, to get high starting pressures. Example underbore cartridges liking this are 6PPC, or 30br.

But regardless of cartridge, changing tension from that load developed with, will likely change results, which may be better or worse.
Don't assume factory annealing is useful to load development. Truly, very little about new brass is useful, and load developing with it doesn't work.

 

[tim_w]

Tim, tension is not a chosen interference fit, nor a seating friction. It's spring back against seated bullet bearing.
Spring back is affected with annealing(typically lowered), so tension is affected with annealing. Tension affects load timing, so you want your load developed at a given tension that you can manage. Some cartridges favor high neck tension, or jammed seating, to get high starting pressures. Example underbore cartridges liking this are 6PPC, or 30br.

But regardless of cartridge, changing tension from that load developed with, will likely change results, which may be better or worse.
Don't assume factory annealing is useful to load development. Truly, very little about new brass is useful, and load developing with it doesn't work.

I understand that tension force and amount of interference are not the same thing so I agree with what you are saying there but increasing the interference does increase tension so while they are tech separate they are also directly related. Thus for a given annealed state if consistent case to case so will the tension be for a given amount of interference. Yes annealing too much can decrease tension to a level where no amount of interference fit may give the needed tension.

My only point is I have never run into a load that needed more tension than a properly annealed case neck could provide with reasonable amount of interference and that with proper annealing it was consistent. But with that said I honestly have not shot that many underbore cartridges and not the ones you mentioned. I have had a gun or two that did seem to shoot well but at higher peak pressure to vel ratio with bullets in the lands a very small amount.

I agree when you change something like this it will have some effect either way if enough resolution is used to see it. I only mentioned new cases as a point of reference for a properly annealed neck. Example being a new lapua case if one was to measure the hardness of the neck area as a good point of reference for a post anneals state goal..

A friend lent be his AMP annealer (I am getting one when I have to return this one as they are AWESOME)while he is deployed and I have used it after each firing and it seems to give very consistent seating force numbers. I want to setup a puller with gauge to see the consistency of these loaded rounds with actual release force. Want to see how well it correlates to seating force consistency and absolute force.

 

[jimbires]

before I started annealing my shoulder length would not be very consistent after resizing . this is on brass that has started to get hard from multiple firings . the question I have for you guys not annealing on a regular basis is , how are you guys dealing with this problem .

 

[Mikecr]

before I started annealing my shoulder length would not be very consistent after resizing . this is on brass that has started to get hard from multiple firings .

Brass doesn't get harder from multiple firings. It gets harder from work hardening, which is SIZING cycles.

On low shoulder angle cartridges, with any area to them, like any 30-06 base, shoulder bumping will eventually be needed. Minimal shoulder bumping at this point will minimize the work hardening of shoulder brass.
So this is still working of shoulders(albeit minimal), and eventually the bumping operation brings pain. This is the time to process anneal shoulders.

Keep in mind also that over annealing(actual annealing) would prevent case shoulders from springing back from chamber shoulders. Normal spring back allows greater cycles between bumps.

With something like a 223Rem, tighter chamber, bumping is less likely ever needed, and so annealing here is never needed -or desired.

 

[Mikecr]

I understand that tension force and amount of interference are not the same thing so I agree with what you are saying there but increasing the interference does increase tension so while they are tech separate they are also directly related. .

There are 3 situations here:
- Full tension is full spring back, and interference needed for full tension is ~1thou under cal.
- If sizing length of necks is beyond seated bullet bearing, then increasing interference beyond spring back increases tension(and increases variance of tension). This, due to binding at bullet base-bearing junction.
-If sizing length of necks is within seated bullet bearing, then increasing interference beyond spring back does not increase tension. You get no more tension than spring back applied to .XXX bearing area, regardless of any greater interference.

If you'd like to see this with your own eyes, there is a simple test.
Partial size down a neck, no more in length than seated bullet bearing. This could be a few thou, -10thou, -50thou if you want(doesn't matter). Seat a bullet, measure loaded neck diameter, pull the bullet, re-measure loaded neck.
You will see that the neck does not spring back to your interference fit. On pulling the bullet, the neck only sprung back ~1thou(max). That is what was gripping the bullet.
All that extra seating force, from excess interference, was just you using a bullet as a neck expander(which you should really stop doing).

 

[Deleted member 46119]

Brass doesn't get harder from multiple firings. It gets harder from work hardening, which is SIZING cycles.

Mike, I gently disagree with this.

The neck expands beyond yield, that is working the brass. The brass balloons beyond yield in the chamber working the brass. Especially the shoulder. Primer pockets that are ruined by hot loads, the primer pocket stretched beyond yield, again that brass was worked.

Physics is physics. If the brass was not worked beyond yeild, we would never have to resize.

 

[Mikecr]

I guess what I'm trying to convey is that where you stop yielding(up or down sizing), you stop hardening. That firing itself does not harden brass or lead to a need for annealing.

Most would probably think this isn't possible, and so a mute point.
But it is possible. You could run a fitted and improved chamber, where brass never yields, never needs sizing, and annealing would never be needed.
Doesn't matter how many times you fire & reload it.

Where this changes, even with example fitted chamber, is when you decide to size that brass. Sizing up and/or down is yielding, which is hardening.

 

[oldfortyfiveauto]

One issue not really discussed here is that using a torch cannot be as consistent as some of the othe processes like induction or dipping. A torch is fine for volume just not the highest accuracy potential.

 

[Deleted member 46119]

One issue not really discussed here is that using a torch cannot be as consistent

I got my molten salt annealing setup but have not used it yet.

Have some stuff for an induction annealer, haven't built it yet.