![]() |
|
Forum Rules | Firearms Safety | Firearms Photos | Links | Library | Lost Password | Email Changes |
Register | FAQ | Calendar | Today's Posts | Search |
![]() |
|
Thread Tools | Search this Thread |
![]() |
#1 |
Senior Member
Join Date: July 12, 2011
Location: Top of the Baltic stack
Posts: 6,079
|
Has my annealing failed and has it banjaxed my accuracy test?
A while back I applied the candle/wet towel annealing method to all my Norma brass. Today I charged and seated 50 of those cases in preparation for a combined Lyman Gen 6/suppressor POI test. I seated all the bullets (Hornady Amax 155gn) with my Lee Handpress.
As I seated the bullets, I noticed that some of the bullets slid in quite easily and others were way firmer to seat. this tells me that my neck tension was not consistent at all. Does this mean that my annealing did not work? Does it also mean that the plan I outlined here is going to suffer due to inconsistencies in neck tension? |
![]() |
![]() |
#2 |
Senior Member
Join Date: February 13, 2002
Location: Canada
Posts: 12,453
|
A candle and a wet towel won't anneal anything. Annealing has nothing to do with neck tension. Check your sizer die/expander.
|
![]() |
![]() |
#3 | |
Senior Member
Join Date: July 12, 2011
Location: Top of the Baltic stack
Posts: 6,079
|
Quote:
As I understand it annealing restores the brass' elasticity which will have an affect on neck tension once it has been put through a sizing die. My sizer die was set the same for all the cases, but they had differing neck tensions. Last edited by Pond, James Pond; June 15, 2015 at 03:02 PM. |
|
![]() |
![]() |
#4 |
Staff
Join Date: March 4, 2005
Location: Ohio
Posts: 21,743
|
James,
The candle heat relieves work hardening stresses. It should not get hot enough to actually soften the brass appreciably, but getting the work hardening out does increase malleability, which is why wildcatters forming cases to significantly different shapes often have to stress relieve the brass to prevent it from splitting. I've had the experience in the past with Remington .45 Auto brass that it got so springy from work hardening after just a couple of reloadings that it would not resize enough to hold a bullet. So, if you have some bullets too easy to seat, it may be not that those cases are soft, but that they were not stress-relieved enough. Note also that stress-relieving will be accompanied by some degree of distortion, so if you didn't resize after annealing, that could be the problem, too. But you posted while I composed so it looks like you did. The thing to do is resize and measure the OD's of the necks as they come out of the sizing die. If some are bigger and some smaller, then you need to note if it is the wider or the narrower ones that are easier to seat. If it is the wider ones, then the cases were not stress-relived enough. If it is the narrower ones, then the cases got too soft, somehow, though it would amaze me if you could do that with a candle. One other possibility occurs to me. The case mouths should be kept tipped up slightly in the candle flame or you may get soot and wax residue condensing inside the neck, and that can act as a lube that would make seating easier. If you got some, it will all burn out on the first firing, but that's probably not what you want to hear, considering the expense involved. You could pull bullets and clean the brass with Q-tips and alcohol, and then run a dry, clean bronze bore brush inside each one for a couple of turns to uniform the surface. If you can, take a chronograph to the range and watch for increased velocity SD compared to what you had before. If you have that, then the seating force variability was probably a good indicator of bullet pull and it is, unfortunately, making a difference.
__________________
Gunsite Orange Hat Family Member CMP Certified GSM Master Instructor NRA Certified Rifle Instructor NRA Benefactor Member and Golden Eagle Last edited by Unclenick; June 15, 2015 at 02:49 PM. Reason: Correction |
![]() |
![]() |
#5 |
Senior Member
Join Date: July 12, 2011
Location: Top of the Baltic stack
Posts: 6,079
|
Well, I have a stack of other cases annealed, sized, trimmed and primed at the same time, so I may measure some ODs on those, find some with a notable difference and seat a bullet, noting which type is easier. Then I can look for the right type for consistent tension so as not to lose my entire batch of uber-carefully metered powder!!
Can I get away with neck sizing on these cases? My collet die lacks a decapping pin: A pain when it happened, but since then incredibly handy at allowing me to pull bullets and reseat them, neck-sizing in between without having to push out a perfectly good primer. |
![]() |
![]() |
#6 |
Senior Member
Join Date: November 22, 2006
Posts: 3,078
|
If you would like to compare how the candle/wet towel method differs from an annealing machine, you can send me some of your brass and I will anneal them for you to test.
|
![]() |
![]() |
#7 | |
Senior Member
Join Date: July 12, 2011
Location: Top of the Baltic stack
Posts: 6,079
|
Quote:
|
|
![]() |
![]() |
#8 | |
Senior Member
Join Date: July 12, 2011
Location: Top of the Baltic stack
Posts: 6,079
|
Quote:
Aaarghh! What a mess!! ![]() My learning curve has been seriously punctuated by peaks and troughs. |
|
![]() |
![]() |
#9 | |
Senior Member
Join Date: July 18, 2008
Posts: 7,249
|
Quote:
F. Guffey |
|
![]() |
![]() |
#10 |
Senior Member
Join Date: July 12, 2011
Location: Top of the Baltic stack
Posts: 6,079
|
I've measured the neck of the remaining cases that I have. None have been fired since being annealed with the method described above. There were a range of external diameters from 8.41mm to 8.50mm, but the vast majority of the 70-odd cases were at 8.46mm and 8.47mm, with further smaller but significant groups at 8.45mm and 8.48mm.
I have measured a few of the complete cartridges and I've seen similar numbers cropping up. It seems therefore likely that the cases are not all bouncing back in the same manner after resizing. In any case, I have taken the 8.46mm neck cases (20 in total), all 25 at 8.47 and 5 from the 8.48mm batch. I will resize them all with the neck collet and clean out the mouths with alcohol and a brush in case of waxy residues from the candle. Once that is done, I will pull all the other bullets and dump the powder in these new cases and then seat fresh bullets (the inertial puller sometimes puts a ding in the polymer tip of Amax bullets which won't help accuracy much). I think that these Norma cases may well be done. Had I done annealing before or had better equipment perhaps they'd be OK, but if they still have not regained they malleability, what good are they to me? It means buying new cases, probably Lapua, and that means a whole new set of load tests to see if a change in case makes an appreciable difference to accuracy. Not what I wanted!! Last edited by Pond, James Pond; June 21, 2015 at 03:01 AM. |
![]() |
![]() |
#11 | |
Member
Join Date: April 17, 2015
Posts: 83
|
Quote:
Plastic deformation is what is supposed to happen when we resize. If the brass didn't deform permanently, you couldn't call it "resizing". If cases are sufficiently work hardened, they will be too elastic and they will tend to spring back toward the original shape. Not completely of course,but at least to some extent. With the force of our presses, even work hardened brass will undergo plastic deformation, but the result is not identical for work hardened brass when compared to annealed brass. When you anneal brass, it becomes softer and more ductile (less elastic) so that when you resize, the brass is reshaped with less "spring back" than it would exhibit had it not been annealed. For this reason, and contrary to some claims in this thread, annealing does indeed have an effect on neck tension. Some people, including me, anneal (with a very precise automatic machine) every time; not so much in an attempt to achieve a particular neck tension but more in an attempt to equalize the neck tension in every case in that all elusive search for consistency which is generally regarded as the holy grail of reloading. Work hardened brass has a higher modulus of elasticity, which is a measure of how "springy" it is. It is also stronger, less ductile, and as far as we're concerned, prone to cracking if deformed one too many times. Bottom line: Annealing will make the cases "less springy", less prone to crack, and (we hope) help produce more consistent neck tension. |
|
![]() |
![]() |
#12 |
Staff
Join Date: March 4, 2005
Location: Ohio
Posts: 21,743
|
Actually, modulus is remarkably constant. It's the tensile strength and yield that move higher and get closer to the ultimate strength of the material, thus making you stress the harder metal more to achieve plastic deformation, but in doing so, coming closer to the point where the brass splits or is otherwise permanently damaged. The same happens with heat treated steels. The really hard stuff has high yield and tensile strength, but is also what we call "brittle", meaning that once you come to the limits of elasticity and strength, you don't have any wiggle room left before hitting the ultimate yield and breaking the material apart. You can see this in the specifications on Matweb by looking at 70-30 cartirdge brass with different tempers. Same with steel. Some tempers have several times the tensile strength and yield of others. But the modulus on an alloy (how many psi it takes to stretch the material a certain percentage) stays the same. The hard stuff just stretches further before plastic deformation, which is why you can make springs from it.
__________________
Gunsite Orange Hat Family Member CMP Certified GSM Master Instructor NRA Certified Rifle Instructor NRA Benefactor Member and Golden Eagle |
![]() |
![]() |
#13 |
Senior Member
Join Date: July 12, 2011
Location: Top of the Baltic stack
Posts: 6,079
|
I've cleaned the mouths and collet sized all the cases I set aside last night. It seems that the cases are now much more uniform.
I sincerely hope that's resolves the variable neck tension issue. If it doesn't, I'm stumped and my accuracy test is dead in the water, so fingers-crossed!! |
![]() |
![]() |
#14 |
Senior Member
Join Date: June 14, 2004
Location: NY State
Posts: 6,575
|
Banjaxed ??? Estonian is certainly a weird language !
Forget the wet towel ! Annealing starts at about 450 F . With a bullet in the case , if you hold it in your hand and can push it down with your thumb you don't have enough neck tension. You may not need an expander .Case neck thickness, expander diameter, bullet diameter are the most important variables. |
![]() |
![]() |
#15 | ||
Senior Member
Join Date: July 12, 2011
Location: Top of the Baltic stack
Posts: 6,079
|
Quote:
The neck tension is not so much an issue of there not being enough to hold the bullet in place, but rather than there seem to be some cases with a much better grip on the bullet than others, meaning pressure variations between those cases with lots of grip and those with less. It's a bit like some cases with no crimp and others a mild crimp. That is probably going to screw with velocities, increasing vertical spread. I realise that the candle technique is not true annealing but I'll quote Unclenick's post from this thread as to the candle heat trick's virtues: Quote:
|
||
![]() |
![]() |
#16 |
Senior Member
Join Date: July 12, 2011
Location: Top of the Baltic stack
Posts: 6,079
|
I have so far pulled 35 of the 50 bullets and only dinged the tip on 6 of them so pretty pleased with that. I have also noticed that the seating pressure needed is waaaaay more uniform so it seems that my "mouthwash" and collet sizing really paid off.
![]() It may mean that from now on, with these Norma cases, I will FL resize then do the collet die too just to be sure that all the necks are as close to the same as possible. It'll hopefully put off buying any new cases for a couple of months. |
![]() |
![]() |
#17 | |
Senior Member
Join Date: December 16, 2013
Location: Eastern NC
Posts: 3,047
|
Quote:
Also, a butane lighter may work better than a candle for cleaner burning, but would cost more A propane torch at the lowest possible setting is another option |
|
![]() |
![]() |
#18 |
Senior Member
Join Date: July 18, 2008
Posts: 7,249
|
Neck tension is not something that locks me up or drives me to the curb. I do not have neck tension, I have bullet hold. R. Lee in his book on modern reloading had a section about bullet hold, I am thinking the short section is right next to the section that covers Federal primers, that is the part where he says "He did not test Federal primers because Federal did not donate primers to be tested.
It had to do with time, as has been suggested pressure and spikes are measured in milliseconds. When we slow down and think about it, it does not take long for the pressure to go from 0-zero to 60 psi. By the time pressure reaches 60 psi all bullets have left, it gets complicated when we add speed. I want all the bullet hold I can get, I measure bullet hold in pounds, I would convert pounds to tensions but there is a problem, I do not have a tensions conversion chart that goes from pounds to tensions. I have fired cases that lost their necks, I have pulled bullets from cases that lost their necks when the bullet was pulled. I have spun cases that split the necks because the neck would not support the tapered spinner. Complicated: The neck of a bottle neck case expands before the bullet leaves, expanding the neck is effortless, think about it? A reloader expands the neck when the ram is lowered and the neck sizing ball is pulled through. I have always thought annealing was governed with simple rules, and now? I still believe annealing is governed by simple rules. F. Guffey |
![]() |
![]() |
#19 |
Senior Member
Join Date: January 16, 2010
Location: Minnesota
Posts: 3,577
|
Did you resize after you annealed?. If not there in lies your whole problem.
|
![]() |
![]() |
#20 | |
Senior Member
Join Date: July 12, 2011
Location: Top of the Baltic stack
Posts: 6,079
|
Quote:
I don't actually know which is the ideal to aim for... SAAMI says 8.72mm or something like that, so clearly that is not what my dies are set to produce! |
|
![]() |
![]() |
#21 |
Senior Member
Join Date: January 16, 2010
Location: Minnesota
Posts: 3,577
|
.002 neck tension is what I set at. Some go .003. Measure one or 2 or more with bullet seated. get a good reading and set neck tension .002 or .003 smaller.
The expander ball coming back out could be the cause of some of the issue. Are you lubing the inside of the neck?. I was told by a wise man- The one thing that throws a neck off is the expander ball being pulled back out of the neck. Pulls up on shoulder and case neck. Also when you are done- Do you run a neck brush down the neck before seating bullet?. Last edited by 4runnerman; June 21, 2015 at 03:07 PM. |
![]() |
![]() |
#22 |
Senior Member
Join Date: July 12, 2011
Location: Top of the Baltic stack
Posts: 6,079
|
TBH, I've yet to reach the stage of being able to adjust those sorts of parameters.
I've only just learnt how to set my shoulders back with the FL die. Now that the FL die is set up, I just run the cases through. I lube the outside, not the inside of the mouth. Is neck tension something that can be set with the collet die rather than the FL die? Last edited by Pond, James Pond; June 21, 2015 at 03:35 PM. |
![]() |
![]() |
#23 | |
Senior Member
Join Date: July 18, 2008
Posts: 7,249
|
Quote:
The wise guys are not difficult to find, in the real world they have shrugged shoulders and receding hair lines. F. Guffey |
|
![]() |
![]() |
#24 |
Senior Member
Join Date: January 16, 2010
Location: Minnesota
Posts: 3,577
|
Guffy- I am but a rookie at most of this ok. I shoot with some of the best shooters I have seen. Ex military sniper, The sniper for the local swat team here, The winner of the Grand Master tourney in Montana. The matches I am in are best of the 5 state area. I take their advice with a grain of salt until I try some of the stuff they say. When my groups shrink from doing them- I simply continue doing it. By doing this I have gone from a MOA shooter to a sub MOA shooter out to 1000 yards now.I have a lot to learn, but I listen,, absorb, and ask questions of those that I see winning matches over and over. As for measuring it- I am sure you have a gauge you made for that, don't you?. Now agree or not the one I can tell you has made a Very big difference ( down this same line). After I run my cases through the die- I pull the expander ball/decapper out and run them through again. This HAS made a noticeable difference in my deviation. My neck tension is perfect from case to case. My deviation from shot to shot is most times 8 FPS or less, the most is 10 FPS.
My effort to seat a bullet is very consistent from one to the next. James- Your full length die should work just fine. I am not positive what would cause your difference in dimensions. My match dies I have sent back to Forester with 5 or more cases and for 10.00 they hone them to your chamber.. Cases must be fired about 4 or more times in your chamber and not resized when you send them in. I have never used a collet die so your one up on me there. |
![]() |
![]() |
#25 | |
Senior Member
Join Date: July 18, 2008
Posts: 7,249
|
Quote:
F. Guffey |
|
![]() |
![]() |
|
|