Neck Tension
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The numbers I give above (OD and neck thickness) are from actual measurements and only the ID is a simple calculation – there is no magic. For each part, I measure 3 times and the numbers are always very close.
As for 5 decimals is beyond the norm for reloading, I hear that all the time but it is not hard to measure to at least 4 decimals (the last one is an average). What is needed is the right tool (expensive Mitutoyo micrometers and tube micrometers both with range down to 0.00005†with accuracy to +/- 0.00015â€) and the right technique. The proof that it can be done are the number you can reproducibly obtained such as its ability to consistently come back to zero and by measuring something that is stable (like the Lee Collet die mandrel) over and over again and being able to get numbers that do not significantly vary.
As for 5 decimals is beyond the norm for reloading, I hear that all the time but it is not hard to measure to at least 4 decimals (the last one is an average). What is needed is the right tool (expensive Mitutoyo micrometers and tube micrometers both with range down to 0.00005†with accuracy to +/- 0.00015â€) and the right technique. The proof that it can be done are the number you can reproducibly obtained such as its ability to consistently come back to zero and by measuring something that is stable (like the Lee Collet die mandrel) over and over again and being able to get numbers that do not significantly vary.
one hundred thousandths....or.....0.00001 is 1/100 of the diameter of a human hair (redhead perhaps)......not to mention how temperature affects measurements this small. Most on this forum will have trouble getting consistent mike readings in the tenths range. This is our annual winter venture into fantasyland.
Thanks Dan.! I am pretty satisfied with my measurements, but honestly not at all satisfied with my brass prep results. My post in Reply #19 was more of a complaint and concern more than anything.
LHSMITH – as mentioned in Repy #21, you can really only measured down close to 0.0001†not 0.00001â€, that last digit is a calculated average. For 0.0001†which is one ten thousands, you don’t really need anything fancy but for 0.00001†you do.
LHSMITH – as mentioned in Repy #21, you can really only measured down close to 0.0001†not 0.00001â€, that last digit is a calculated average. For 0.0001†which is one ten thousands, you don’t really need anything fancy but for 0.00001†you do.
jlow--Even if you size w/ the Lee Collet Die, if you would take your exhaustive measurements of the ids after you size w/ a hole gauge or something more positive (no calculating because the outside of the wall is iregular, not even) and keep them as close as possible to one another then neck turn then not the next day, I believe you will be satisfied. Have different mandrels on hand polished to different diameters and your expand mandrel and holder set up in the press to reopen the mouth if needed or use a larger mandrel to reopen mouth until to achieve very close ids. If you have to turn or polish a spare expand mandrel down some to achive this, this is where IMHO people are screwing up. Just running the case mouth into a exp mandrel and neck turning don't get it for me but if they get good results ok.
Thanks for following up, so a few more questions from this noob! 
One is in terms of sizing with a hole gauge for a direct measurement, the only hole gauge I have is a set of those Starrett No. S 831 E small hole gages. I have to be honest but I have never really have been too comfortable using them since their adjustment seems a bit coarse? Is there a trick to using them?
Also in my case, I neck turned before I use the Lee Collet die on them since sizing with the Lee Collet die is my final step in brass prep – at least that is the plan… Is this incorrect?
As to opening them up afterwards with a mandrel (at least I think this is what you mean?), it does seem to reduce the amount of variance but at least for me using only a single size mandrel gives better but still not real satisfactory results. Are you saying I need a number of different mandrels with different diameters? Can you tell me why that would work better?
In terms of the neck turning mandrel, I am using both the K&M expander and neck turning mandrel and they seem to work since I am as mentioned earlier, I am only getting a 0.00015†variance on neck thickness (that is measuring 3 times around the neck with little variance within a case) with 28 cases and SDEV of 0.00003â€. All cases annealed as per proper directions with BenchSource annealer.
One is in terms of sizing with a hole gauge for a direct measurement, the only hole gauge I have is a set of those Starrett No. S 831 E small hole gages. I have to be honest but I have never really have been too comfortable using them since their adjustment seems a bit coarse? Is there a trick to using them?
Also in my case, I neck turned before I use the Lee Collet die on them since sizing with the Lee Collet die is my final step in brass prep – at least that is the plan… Is this incorrect?
As to opening them up afterwards with a mandrel (at least I think this is what you mean?), it does seem to reduce the amount of variance but at least for me using only a single size mandrel gives better but still not real satisfactory results. Are you saying I need a number of different mandrels with different diameters? Can you tell me why that would work better?
In terms of the neck turning mandrel, I am using both the K&M expander and neck turning mandrel and they seem to work since I am as mentioned earlier, I am only getting a 0.00015†variance on neck thickness (that is measuring 3 times around the neck with little variance within a case) with 28 cases and SDEV of 0.00003â€. All cases annealed as per proper directions with BenchSource annealer.
It’s a good thought about annealing more to see if that would help with consistency and it had actually occurred to me last week and I ran the following small experiment.
First, I gathered 32 pieces of off centered cases which had been culled but neck turned to have neck thickness with a range of 0.00025†(SDEV 0.00007â€). I surveyed the brass OD to find the ones which had inconsistent OD of at least 0.00025†(the idea was these would be the ones not yet properly annealed). I randomly group these 15 pieces of brass into 5 groups of three cases.
Started to anneal the first group with 0.2 seconds (2.4 seconds) less than the optimal amount of annealing time for the torch setup, the next groups were 2.6 (optimal), 2.8, 3.0, and 3.2 seconds. The last one was long enough to see the necks definitely glow red.
After annealing, the cases were neck sized with the Lee Collet die and then their OD measured. My thought was I would see softer necks in those which had definitely been over-annealed and these would sized more evenly and thus have a more consistent ID/OD. Unfortunately I found absolutely no decrease in ID/OD variance with increase in annealing.
Now I was only 0.6 seconds over annealed at the longest time point but that would seemed to be quite a bit especially considering that those had clearly red glowing necks.
BTW, I tried to use an IR temperature reader to find the case temps but was not successful. However, I did put a full length strip of 400 degree Tempilaq on the outside of each case and although the Tempilaq was not affected within 1†of the case head at the start (as per recommended by BenchSource), increases in annealing time reduce the length of the unaffected Tempilaq stepwise and by the last condition i.e. 3.2 seconds annealing time, the distance where the Tempilaq had cleared was reduced to 0.5 -0.6†from the case head, so those were definitely over annealed.
So I don’t know….
First, I gathered 32 pieces of off centered cases which had been culled but neck turned to have neck thickness with a range of 0.00025†(SDEV 0.00007â€). I surveyed the brass OD to find the ones which had inconsistent OD of at least 0.00025†(the idea was these would be the ones not yet properly annealed). I randomly group these 15 pieces of brass into 5 groups of three cases.
Started to anneal the first group with 0.2 seconds (2.4 seconds) less than the optimal amount of annealing time for the torch setup, the next groups were 2.6 (optimal), 2.8, 3.0, and 3.2 seconds. The last one was long enough to see the necks definitely glow red.
After annealing, the cases were neck sized with the Lee Collet die and then their OD measured. My thought was I would see softer necks in those which had definitely been over-annealed and these would sized more evenly and thus have a more consistent ID/OD. Unfortunately I found absolutely no decrease in ID/OD variance with increase in annealing.
Now I was only 0.6 seconds over annealed at the longest time point but that would seemed to be quite a bit especially considering that those had clearly red glowing necks.
BTW, I tried to use an IR temperature reader to find the case temps but was not successful. However, I did put a full length strip of 400 degree Tempilaq on the outside of each case and although the Tempilaq was not affected within 1†of the case head at the start (as per recommended by BenchSource), increases in annealing time reduce the length of the unaffected Tempilaq stepwise and by the last condition i.e. 3.2 seconds annealing time, the distance where the Tempilaq had cleared was reduced to 0.5 -0.6†from the case head, so those were definitely over annealed.
So I don’t know….
jlow--Just try shooting at a long range on a good condition. That will tell you what is working and what is not in your reloading process, much better than a chronograph too. Just make sure the barrel is fouled w/ a couple of foulers, go to town w/ 20 or 30 rounds (5 shot groups) then clean refoul a go again. The stuff that isn't up to par will be out of the accuracy spectrum, you can use for foulers and the good stuff remains. Vertical is what counts at long range. Then you can check your measurments and see if they add up. I forgot what caibers you shoot but go to the extreme distance w/ those calibers. A day or two at the range will surely answer a lot of your queries.
Hi Dan,
It’s good advice but unfortuantely that is where I came from originally. My MV SDEV is in the 20s which is what I am not so happy with i.e. the problem with vertical stringing.
Despite being a type A, I have learned not to sweat the small stuff unless it really matters. My problem here is I am not quite sure what the source of the problem is and thus doing all this nitpicking....
It’s good advice but unfortuantely that is where I came from originally. My MV SDEV is in the 20s which is what I am not so happy with i.e. the problem with vertical stringing.
Despite being a type A, I have learned not to sweat the small stuff unless it really matters. My problem here is I am not quite sure what the source of the problem is and thus doing all this nitpicking....
jlow said:
Those can't be realistic numbers! If you're really capable of that kind of accuracy you've got to have spent more money on measuring tools that you have on the hardware you shoot with!
http://en.wikipedia.org/wiki/Significant_figures
Too hot if they're visibly incandescent.
You don't NEED to get them that hot to get decent annealing accomplished, at least for our purposes. The rest of your post clearly supports this.
I mentioned my annealing practices earlier on. I get SD's <5 most of the time for tuned loads for Palma ammo this way. I admit I turn case necks to 0.012" too which seems to help....
This is sad. Before you continue, you should to read the whole thread and not just one post. That way you understand what and why we are talking about and don’t ask the same questions that had been asked and answered already.
I find it interesting that people say that you are doing something impossible but don’t give any reason why they say this except that they cannot believe it – that my friend is not constructive. As I mentioned above in Reply #21 “As for 5 decimals is beyond the norm for reloading, I hear that all the time but it is not hard to measure to at least 4 decimals (the last one is an average). What is needed is the right tool (expensive Mitutoyo micrometers and tube micrometers both with range down to 0.00005†with accuracy to +/- 0.00015â€) and the right technique. “ BTW, the capability of the micrometer I quoted is from the manufacturer.
The tools are of course expensive:
http://www.amazon.com/gp/product/B001VXNYW6/ref=oh_details_o01_s00_i00
http://www.amazon.com/gp/product/B001C0XY2S/ref=oh_details_o06_s00_i00
But why is that bad? As to being more expensive that my guns, well you are in the wrong group if you think so....
As for “significant figuresâ€, well I guess I should know this by now since I have 30 years in research and have been preached this umpteen time when I was a young graduate student. FWIW, the number 0.00025†I used above only have one real significant figure “2†with the last one an extrapolated average. Just because there are 6 numbers there does not mean they are all significant. This is the same reason why the number 2,500,000,000 really only have two significant figures….
As to the brass being “too hot†well, I guess I can only ask you to read my post in Reply #30 CAREFULLY again. If you are still confused, I will be happy to answer you question.
Sorry if I seemed a bit miffed :but it does get a bit tiring when people post questions when they don’t bother to read what you have taken a lot of time and effort to answer questions and explain rationales.
I find it interesting that people say that you are doing something impossible but don’t give any reason why they say this except that they cannot believe it – that my friend is not constructive. As I mentioned above in Reply #21 “As for 5 decimals is beyond the norm for reloading, I hear that all the time but it is not hard to measure to at least 4 decimals (the last one is an average). What is needed is the right tool (expensive Mitutoyo micrometers and tube micrometers both with range down to 0.00005†with accuracy to +/- 0.00015â€) and the right technique. “ BTW, the capability of the micrometer I quoted is from the manufacturer.
The tools are of course expensive:
http://www.amazon.com/gp/product/B001VXNYW6/ref=oh_details_o01_s00_i00
http://www.amazon.com/gp/product/B001C0XY2S/ref=oh_details_o06_s00_i00
But why is that bad? As to being more expensive that my guns, well you are in the wrong group if you think so....
As for “significant figuresâ€, well I guess I should know this by now since I have 30 years in research and have been preached this umpteen time when I was a young graduate student. FWIW, the number 0.00025†I used above only have one real significant figure “2†with the last one an extrapolated average. Just because there are 6 numbers there does not mean they are all significant. This is the same reason why the number 2,500,000,000 really only have two significant figures….
As to the brass being “too hot†well, I guess I can only ask you to read my post in Reply #30 CAREFULLY again. If you are still confused, I will be happy to answer you question.
Sorry if I seemed a bit miffed :
but it does get a bit tiring when people post questions when they don’t bother to read what you have taken a lot of time and effort to answer questions and explain rationales.jlow said:
Actually it is quite difficult to measure that small. Most people on this forum will have trouble getting consistent readings in the tenths range, and to measure smaller you better be in a controlled environment and use more sophisticated lab equipment AND trained and adept in their use.
If for some reason you feel compelled to take your tension experiment into the lab, feel free. i just want to know what you will do with the necks after firing and the numbers start moving all over the place...re-turn the necks? ..only shoot the brass 1x?
Also, after reading post #30...I have to agree that unless one reads the entire post very carefully, it mentions heating until necks are red TWICE....which we all know is BAD..... but for the new guy just learning annealing and scanning posts while doing a search.......I can see a potential problem.
LHSMITH said:
And another thing, to what decimal place and tolerance are your bullets being made to?
Plus other points to ponder....how round is your expander able to make the case neck?.. how uniform can you cut the necks?.might need to consider measuring the following also: cylindricity, circularity, & circular run-out... for instance some cases may retain an egg shape after all the operations, others may not...this surely will affect the tension felt during seating.
Don't do these measurements on my behalf....I just accept brass to be it's squirrelly self and live with it.....cuz they ain't gonna all react the same way after firing..even if from same lot,same anneal, same pressures without culling
I have already explained why it is possible for me to make measurements with the instruments in question and so there is really no sense in going through that again. Instead, please let me share something that I have learned that relates to the current discussion.
The internet is the wild west of the 21st century and you are always going to run across someone or something that sounds too good or is unbelievable. Certainly some people are going to make exaggerated and wild claims, it is unavoidable - my advice is to just ignore them. Some people also make mistakes and if it is worth your while, it might be nice to point out their mistake if you are sure of your knowledge and answer. Sometimes people can just do things that you and I cannot do. This could be something as simple as running faster, shoot more accurately or as I lamented earlier on reload rounds with single digit MV SDEV.
Now, when this happens, we can look at this as a deficiency in ourselves or on a positive side as something that is actually possible (someone has done it right?) and so something to strive towards. What is clear to me is looking at this as something negative is counterproductive as for any one thing that I can do better than most, there are billions of things that other people can do better than me. So look at this as something negative would certainly be depressive, so why go there?
As a research scientist, I have spent my life trying to answer questions. What I have found is to do this effectively, I need to address each potential variable to the best of my ability. In this case, I learn to turn my necks as best as I can, not because I know it is necessary but because it will allow me to discard it as my problem should it not solve the issue on hand. In the mean time, I have taught myself how to neck turn in a very reproducible fashion and a way to measure the results. Having this knowledge on hand, I can then use it to evaluate other variables such as variation in neck ID, so why is this bad? The correct answer is it is not.
As you correctly pointed out, there are many potential variables that are not controlled, so one can throw one’s hands up or you can do as I am trying to do which is do your best to find the path forward and at the same time enjoy the journey. Just remember, if you wake up tomorrow and can reload and shoot one hole strings all day at any distance under any condition, it would completely ruin this as a sport for you.
The internet is the wild west of the 21st century and you are always going to run across someone or something that sounds too good or is unbelievable. Certainly some people are going to make exaggerated and wild claims, it is unavoidable - my advice is to just ignore them. Some people also make mistakes and if it is worth your while, it might be nice to point out their mistake if you are sure of your knowledge and answer. Sometimes people can just do things that you and I cannot do. This could be something as simple as running faster, shoot more accurately or as I lamented earlier on reload rounds with single digit MV SDEV.
Now, when this happens, we can look at this as a deficiency in ourselves or on a positive side as something that is actually possible (someone has done it right?) and so something to strive towards. What is clear to me is looking at this as something negative is counterproductive as for any one thing that I can do better than most, there are billions of things that other people can do better than me. So look at this as something negative would certainly be depressive, so why go there?
As a research scientist, I have spent my life trying to answer questions. What I have found is to do this effectively, I need to address each potential variable to the best of my ability. In this case, I learn to turn my necks as best as I can, not because I know it is necessary but because it will allow me to discard it as my problem should it not solve the issue on hand. In the mean time, I have taught myself how to neck turn in a very reproducible fashion and a way to measure the results. Having this knowledge on hand, I can then use it to evaluate other variables such as variation in neck ID, so why is this bad? The correct answer is it is not.
As you correctly pointed out, there are many potential variables that are not controlled, so one can throw one’s hands up or you can do as I am trying to do which is do your best to find the path forward and at the same time enjoy the journey. Just remember, if you wake up tomorrow and can reload and shoot one hole strings all day at any distance under any condition, it would completely ruin this as a sport for you.
My problem is your claim that it is simple for anyone to measure to 0.00001 with the proper micrometer. This is not true. A trained QA inspector in a lab -yes. You make no mention of what tool you are using, nor the procedures...did you do this in a lab with a comparitor?
I don't think it helps forum members who are just getting into the neck-turning/ annealing part of accurate reloading by making it appear harder than really is. And someone just getting the necessary equipment might think he needs a $400 micrometer.
You never addressed my questions from the post above......when your talking THAT small .....you had better address the roundness,( or ovality if you will) of the necks or your data will be compromised. What are you using to measure bullet seating force that is that precise?
By not taking into consideration the bullet tolerance and roundness...your whole exercise is futile IMHO.
I don't think it helps forum members who are just getting into the neck-turning/ annealing part of accurate reloading by making it appear harder than really is. And someone just getting the necessary equipment might think he needs a $400 micrometer.
You never addressed my questions from the post above......when your talking THAT small .....you had better address the roundness,( or ovality if you will) of the necks or your data will be compromised. What are you using to measure bullet seating force that is that precise?
By not taking into consideration the bullet tolerance and roundness...your whole exercise is futile IMHO.
LHSMITH, you seemed to have that 0.00001 number stuck in your mind.LHSMITH said:
If you look at what I said in Reply #21 (and again in Reply #24!) I clearly said to you and I will quote myself yet a second time “you can really only measured down close to 0.0001†not 0.00001â€, that last digit is a calculated average. For 0.0001†which is one ten thousands, you don’t really need anything fancy but for 0.00001†you do.†So it is really hard for me to understand why you keep trying to say that I said I can measure to 0.00001â€??????
As for it not helping form members by making it appear harder, notice I was not the first poster to come up with these numbers, it was in fact normmatzen in Reply #13. My own first post in this thread i.e. Reply #19 was to put what I throught was a proper prospective into this number and I quote myself again here which was not a boast but to say “this sounds better than it actually is†and go on to explain why? This instead of the other interviening post which only made fun of normmatzen without adding anything to the conversation.
As for addressing the roundness, here I agree with you i.e. it is a BIG problem. Let me put my instructor hat for a second here and ask you to think about this for a second. If I come to you and said “hey, I measured the outside diameter of my neck in three locations and the numbers don’t agree with each other by this much and I am concerned!†Well the first question that should come to your mind should be is the problem an inconsistency in neck thickness? Or is the neck out of round? They both can cause the same symptom but unless you know which one is culprit how can you find a fix? Well the answer for me is if I can cut my neck precisely and be able to measure it and proof that the neck thickness is very even, then I know the problem is in fact the neck is out of round. Once I figured this out, I can concentrate my efforts into making the case rounder. This is in fact what I did.
Please tell me why this does not make sense to you?
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