annealing frequency when only neck sizing

[fyrewall]

Yes, the graphs shown on the che.uri are in minutes, up to 45 at 400 C or 752 F. The single serving crock pot molten salt bath U tube specifies 500-550 C or 932 - 1022 F for 4-7 seconds and shows cases rapidly being dunked then extracted alternately so 4-7 seconds is not a misspeak. Not knowing much about annealing there seems to be a big discrepancy between che.uri and the molten salt crock pot like 55 to 1. Four to seven seconds sounds to good to be true.

At this time I am toasting my necks for 30 seconds at 2000 C using a circular propane torch tip - a guess. Things seem to work well, no split necks after annealing. I turn necks and use Forster F/L dies that have had the neck area enlarged, the idea being to reduce the amount the neck portion is worked during sizing. I get good accuracy and bullets can be slip fitted into fired case mouths and bullets are securely held in loaded rounds.

I don't have a clue of the actual neck hardness after annealing. I use a cookie sheet (Walmart) with 1/2 inch of water to hold cases while annealing then tip them over (sizzle). I usually anneal after 3 or 4 cycles.

 

[mikecr]

Dipping times are accurate, the linked junk is wrong.

 

[msinc]

Not sure I get the difference between neck sizing vs. full length in regards to annealing....isn't the neck the part that gets worked the most either way???? I mean, if you are sizing to your chamber length or very close to it {not sure why anyone wouldn't} the neck is getting worked either way. You might be able to do it less often if using a Lee collet type die.
All that said, I typically anneal every 4th or 5th time. In cases with larger, say 7mm and up, I can generally "feel" the expander ball getting tighter or harder to pull thru the neck. On new {to me} cases such as range brass, or military brass with older year stamps {like from the 50's or earlier} I can sometimes hear the neck make kind of a chirping noise as it passes over the expander if the brass is really in need of annealing. UNless someone else has done it older brass almost always needs annealed.

 

[Pigdog]

Pigdog,
I'm not fond of only Neck Resizing. Have tried it before and compared the two results, accuracy wise. Where I found the advantage to FL resizing OVER just Neck Sizing is in Concentricity. The runout in FL Resized brass was better than casings that I just Neck Sizing. But as to annealing....I'm an accuracy freak. but no longer compete. And I use strictly Lapua brass because it is the most consistent brass from piece to piece. To that end, like you, I hand anneal all my brass. I use an annealing kit that Hornady used to sell and insert the case holder in an electric screw driver that has low RPM and have learned the timing (different times depending on the size of the casing) to hold the neck junction in the flame of a simply torch that uses coleman latern gas bottles. And considering I only shoot and resize no more than 50 casings (usually around 40) at a time, those fancy Annealers are overkill (in expense) for my low volume of casings I work at any one time. As far as frequency, I anneal every third resizing to keep the brass lively. On my 6br, I'm now on #33 resizing using the same Lapua brass. Works for me.

Alex

Hi alex the guy I brought my rifle off gave me a Wilson neck sizer die so I have just rolled with that since. Like you I only work with 50 pieces of lapua brass and with the drill it takes bugger all time to anneal them. I just was more unsure as to whether doing it every time would do more harm than good as I'm not working the brass much at all other than the Wilson neck die but I would be more than happy to anneal after every firing to keep my brass living longer it is all neck turned as well.

 

[JebWV]

"recrystallization"

The graph shows hardness as RT30. Samples with a RT30 of 75 became softer than those with a RT30 of 55 after only 20 or so minutes but those with an RT30 of 55 maintained a constant hardness . To me this would indicate the less worked brass had less grain growth and maintained hardness. Highly worked brass had greater grain growth over time at 400 C and had more hardness changes.

Key words - "shooters", "studied metallurgy", "months and years at room temperature", "high temperature", "rocket surgery", "things college students do"

This is consistent with my experiences as a metallurgist. Relaxation and recrystallization requires an amount of residual strain energy from cold work to drive the kenetics. The higher the stored strain energy, the faster the recrystallization can occur or it can occur at the same rate at a lower temperature. High residual strain energy and lower annealing temperatures will produce a fully recrystallized product with a small grain size. Low strain energy will result in a lower percent of recrystallized metal after annealing. High annealing temperatures or very long annealing times will produce a grain coarsening. In order to keep the most consistent microstructure in the neck for each reload, I think I'd anneal every time, but prior to annealing, run the necks through the sizing die 4 or 5 times to ensure they had enough cold work to adequately respond to the anneal.

 

[Shynloco]

Hi alex the guy I brought my rifle off gave me a Wilson neck sizer die so I have just rolled with that since. Like you I only work with 50 pieces of lapua brass and with the drill it takes bugger all time to anneal them. I just was more unsure as to whether doing it every time would do more harm than good as I'm not working the brass much at all other than the Wilson neck die but I would be more than happy to anneal after every firing to keep my brass living longer it is all neck turned as well.

Pdog,
For what it's worth, my annealing every third shooting of my brass has gotten me to 33 times reloads so far without any necks cracking. Also consider, most of the shooters who resize every time are the true competitors who are trying to make their brass perfect. And I'm told, they have NO intention or expectation that their brass will last probably more than 10 or 12 shootings. They retire their brass at an unbelievably high rate compared what I do. The cost of their brass is nothing to them because many have sponsors who pay for most of their toys. So for our purposes, every third time is plenty and my brass works just fine at that rate. But each to his own.

Alex

 

[Pigdog]

Thanks Alex I think I will roll
With every 3rd time. I'm just looking to extend brass life mainly as like you I pay for all my stuff and this stuff gets expensive

 

[4xforfun]

OK...so ...I am confused. (So, whats new!!). Anyway...why would it make a lick of difference weather he FL sizes or neck sizes when it comes to weather of not...or how often....you anneal? The purpose of annealing is to give proper, and thus, the same, bullet release from the neck....and to avoid cracking of the neck. We must assume that weather you FL size or neck size that you are using the same bushing...and...shooting out of the same gun. The focus is on the neck, not the shoulder, or 1/2 inch below the shoulder, or whatever.

A side benefit of proper annealing is softening of the shoulders to keep them from cracking.

In short, it doesn't matter HOW you size...full or neck.... The necks are worked the same either way.

What say you?
Tod

 

[riflewoman]

That lab report has bounced around this forum before. The information in it is correct, BUT, the conclusions drawn from it may be misleading. I was an aerospace design engineer and I also worked alongside some pretty good metallurgists. I think I asked them about this very topic a long time ago and after reading their “Metals Handbook” I came to some conclusions.

The purpose of annealing at very low cold work levels (1 firing) is to get consistent bullet release. I suppose it can work well however I’m not really sure how it can be verified. Seating force is a poor indicator of bullet pull for a bunch of reasons. And I’m also not sure that the neck expansion doesn’t occur first so there is no “pull” to begin with. If you think it works, fine. But it may not really be the cause for your accuracy.

The three things that happen during annealing (relaxation, recrystallization and grain growth) are temperature AND time dependent. At very low temperatures it may take several seconds or even hours to get sufficient relaxation. At higher temperatures it takes much less time. Recrystallization also must have significant amount of cold work energy stored for it to happen. The consensus amongst metallurgists is that the recrystallization takes place at dislocations and at “slips” at the grain boundaries. The more there are the faster it recrystallizes and the finer the grain. For brass it appears that 40% accumulated cold work has a good amount of cold work to get recrystallization at the 800 to 900F temperatures needed for flash annealing. Grain growth happens after recrystallization. Quenching stops grain growth.

All that above indicates that the old process of heating to a VERY dull red glow ( so little you need to work in the dark) with an immediate tip into water gives good results. Especially for amateurs.

To get to the magic 40% cold work you have to know how much you reduce or expand during each resize, expand, bullet seat, and firing. For say a 223 with normal dies that’s about 3 firing cycles. For bushing dies, turned necks and all that, it may be more.

As always,, YMMV.

 

[fyrewall]

This amateur uses a propane torch and avoids working brass excessively to avoid split necks using turned necks and Forster F/L dies having honed out necks. I like to see the necks turn dull red and hear them sizzle upon tipping them over. Turning the cases using my DeWalt cordless lends some pleasure to the process.

I seem to remember seeing a link where brass hardness was maintained at a certain level independent on toasting time at constant 500 C or 900 F.

Would it be a reasonable guess that some brass like Lapua might be manufactured having a some cold work near 40 %?

On certain "salt annealing devices" immersion times of 4-7 seconds in molten salts are provided. I take it this would be the "relaxation" phase of the process and any re-crystallization would be dependent on past over time "cold work energy".

I try to turn necks so I can get a bullet slip fit into a fired case and have bullets securely held but hold cold working to a minimum. I toast my necks every 4-5 firings using a propane torch for 30 seconds. The results appear to be adequate but are just "trial and error".

Neck turning is not an option when making 6.5-06 out of .30-06 because of thick neck walls and no room for expansion and I would guess the neck size reduction from .30 - .26 would make for lots of cold working.

 

[seymour fish]

as the title suggests how often are yall annealing when only neck sizing? I enjoy the reloading process and enjoy annealing I do it by hand and would like to do it after every firing. I'm just concerned that it might be over doing it when I'm only neck sizing?? thoughts?

You can try never. Course I never won shit, ......but still

 

[Webster]

OK...so ...I am confused. (So, whats new!!). Anyway...why would it make a lick of difference weather he FL sizes or neck sizes when it comes to weather of not...or how often....you anneal? The purpose of annealing is to give proper, and thus, the same, bullet release from the neck....and to avoid cracking of the neck. We must assume that weather you FL size or neck size that you are using the same bushing...and...shooting out of the same gun. The focus is on the neck, not the shoulder, or 1/2 inch below the shoulder, or whatever.

A side benefit of proper annealing is softening of the shoulders to keep them from cracking.

In short, it doesn't matter HOW you size...full or neck.... The necks are worked the same either way.

What say you?
Tod

Never saw a cracked shoulder in 45 years.

 

[Webster]

That lab report has bounced around this forum before. The information in it is correct, BUT, the conclusions drawn from it may be misleading. I was an aerospace design engineer and I also worked alongside some pretty good metallurgists. I think I asked them about this very topic a long time ago and after reading their “Metals Handbook” I came to some conclusions.

The purpose of annealing at very low cold work levels (1 firing) is to get consistent bullet release. I suppose it can work well however I’m not really sure how it can be verified. Seating force is a poor indicator of bullet pull for a bunch of reasons. And I’m also not sure that the neck expansion doesn’t occur first so there is no “pull” to begin with. If you think it works, fine. But it may not really be the cause for your accuracy.

The three things that happen during annealing (relaxation, recrystallization and grain growth) are temperature AND time dependent. At very low temperatures it may take several seconds or even hours to get sufficient relaxation. At higher temperatures it takes much less time. Recrystallization also must have significant amount of cold work energy stored for it to happen. The consensus amongst metallurgists is that the recrystallization takes place at dislocations and at “slips” at the grain boundaries. The more there are the faster it recrystallizes and the finer the grain. For brass it appears that 40% accumulated cold work has a good amount of cold work to get recrystallization at the 800 to 900F temperatures needed for flash annealing. Grain growth happens after recrystallization. Quenching stops grain growth.

All that above indicates that the old process of heating to a VERY dull red glow ( so little you need to work in the dark) with an immediate tip into water gives good results. Especially for amateurs.

To get to the magic 40% cold work you have to know how much you reduce or expand during each resize, expand, bullet seat, and firing. For say a 223 with normal dies that’s about 3 firing cycles. For bushing dies, turned necks and all that, it may be more.

As always,, YMMV.

Nice response. I was involved with metallurgical failure analysis and material compliance for forty five years. Almost all of the reports quoted have close to zero value since we don't know the % of cold work after firing and sizing. Many of the articles have charts up to 40% cold work. We don't know if cartridge necks approach that level. Annealing times in minutes have no value comparing to flash annealing for seconds. I would like to see a similar test with % cold work of 1%, 5%, 10% and times of 5, 10 and 15 seconds at about 5 temperatures. I have done flash annealing in a lab furnace for short times on Lapua case necks and determined the hardness without knowing the % cold work. I put the data on this website at least 4 times.

Bottom line is we know pretty much what temp and time to anneal. You just have to accept the results and quit worrying about it. If you are not shooting serious comp it does not matter if you have consistent neck tension. I have a 6BR and a 6BRX with Kreiger barrels for varmint hunting. Both will shoot groups under .350" with or without annealing with my poor shooting skills.

 

[dolek]

Nice response. I was involved with metallurgical failure analysis and material compliance for forty five years. Almost all of the reports quoted have close to zero value since we don't know the % of cold work after firing and sizing. Many of the articles have charts up to 40% cold work. We don't know if cartridge necks approach that level. Annealing times in minutes have no value comparing to flash annealing for seconds. I would like to see a similar test with % cold work of 1%, 5%, 10% and times of 5, 10 and 15 seconds at about 5 temperatures. I have done flash annealing in a lab furnace for short times on Lapua case necks and determined the hardness without knowing the % cold work. I put the data on this website at least 4 times.

Bottom line is we know pretty much what temp and time to anneal. You just have to accept the results and quit worrying about it. If you are not shooting serious comp it does not matter if you have consistent neck tension. I have a 6BR and a 6BRX with Kreiger barrels for varmint hunting. Both will shoot groups under .350" with or without annealing with my poor shooting skills.

Great reply,I agree 100% all this opinionated talk means nothing without facts...and without knowing for certain at what percentage the brass has been work hardened you will never know all the facts .

Is there a scale to test work hardened brass,like a Rockwell test for brass?

 

[dickn52]

Anneal every time and be done with the worrying part. If done right you won't hurt the brass, and you can only improve it if they need it.