Does a concentricity gauge indicate anything about neck tension? I use Lapua brass and have never neck turned them. Most have been fired at least 5 times. I use Forster NS and bullet seating dies, and checking with a concentricity gauge, I seldom find any that have over .001 runout. No complaints with that, just wondering if this would indicate that I have no neck tension problems....??
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Neck Tension vs Concentricity
- Thread starter jkonzal
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Re: Neck Tension vs Concentricity
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Flintlock Shooter</div><div class="ubbcode-body">Does a concentricity gauge indicate anything about neck tension? I use Lapua brass and have never neck turned them. Most have been fired at least 5 times. I use Forster NS and bullet seating dies, and checking with a concentricity gauge, I seldom find any that have over .001 runout. No complaints with that, just wondering if this would indicate that I have no neck tension problems....?? </div></div>
There are more than a few things that can affect runout, but I don't know if neck tension is one of them.
I guess if you're using a bushing die and you have some oval shaped bushing, that might pinch the necks a bit and maybe tilt the bullet, but ehhh...
There are enough posts here that will address runout that I'm not going to get into them. Suffice it to say, if you're getting .001" T.I.R. as a rule, don't muck with things.
If it ain't broke...
Chris
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Flintlock Shooter</div><div class="ubbcode-body">Does a concentricity gauge indicate anything about neck tension? I use Lapua brass and have never neck turned them. Most have been fired at least 5 times. I use Forster NS and bullet seating dies, and checking with a concentricity gauge, I seldom find any that have over .001 runout. No complaints with that, just wondering if this would indicate that I have no neck tension problems....?? </div></div>
There are more than a few things that can affect runout, but I don't know if neck tension is one of them.
I guess if you're using a bushing die and you have some oval shaped bushing, that might pinch the necks a bit and maybe tilt the bullet, but ehhh...
There are enough posts here that will address runout that I'm not going to get into them. Suffice it to say, if you're getting .001" T.I.R. as a rule, don't muck with things.
If it ain't broke...
Chris
Re: Neck Tension vs Concentricity
Neck turning does two things. First it allows a precise fit in a tight match chamber/neck. Second, it makes it possible to take the wall thickness variation out of the necks. My last batch of Lapua 260 Rem brass had some necks that measured from 0.015" to 0.017". Turned them all to 0.015".
Even wall thickness doesn't hurt concentricity and probably helps a bit, but as already posted there are a lot of variables involved.
OFG
Neck turning does two things. First it allows a precise fit in a tight match chamber/neck. Second, it makes it possible to take the wall thickness variation out of the necks. My last batch of Lapua 260 Rem brass had some necks that measured from 0.015" to 0.017". Turned them all to 0.015".
Even wall thickness doesn't hurt concentricity and probably helps a bit, but as already posted there are a lot of variables involved.
OFG
Re: Neck Tension vs Concentricity
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Flintlock Shooter</div><div class="ubbcode-body">I seldom find any that have over .001 runout. </div></div>you should sell your secret
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Flintlock Shooter</div><div class="ubbcode-body">I seldom find any that have over .001 runout. </div></div>you should sell your secret
Re: Neck Tension vs Concentricity
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: MALLARD</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Flintlock Shooter</div><div class="ubbcode-body">I seldom find any that have over .001 runout. </div></div>you should sell your secret </div></div>
There's no secret just good dies well setup. I typically see 0.000"-0.0015" TIR on unturned cases loaded on my 30 year old modified Dillon 550 press. Of course that is using the Dillon 550 one station at a time not as a progressive press.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: MALLARD</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Flintlock Shooter</div><div class="ubbcode-body">I seldom find any that have over .001 runout. </div></div>you should sell your secret </div></div>
There's no secret just good dies well setup. I typically see 0.000"-0.0015" TIR on unturned cases loaded on my 30 year old modified Dillon 550 press. Of course that is using the Dillon 550 one station at a time not as a progressive press.
Re: Neck Tension vs Concentricity
Flint,
I don't think concentricity has anything to do with neck tension. Like others have stated above, start looking at your die setup(s).
Flint,
I don't think concentricity has anything to do with neck tension. Like others have stated above, start looking at your die setup(s).
Re: Neck Tension vs Concentricity
If you are concerned about neck tension, measure the inside diameter of the case mouth after you have sized the neck. That will tell you if your neck tension is consistent.
For example, on my .308 brass, my finished ID on the neck after sizing is .305 (.003" neck tension).
After reading the Houston Warehouse article I started checking this because some bullets seemed to require more force to seat than others as I was loading. I discovered that my neck tension was not as consistant as I thought and made some changes in my case prep and sizing proceedures to help resolve the problem.
If you are concerned about neck tension, measure the inside diameter of the case mouth after you have sized the neck. That will tell you if your neck tension is consistent.
For example, on my .308 brass, my finished ID on the neck after sizing is .305 (.003" neck tension).
After reading the Houston Warehouse article I started checking this because some bullets seemed to require more force to seat than others as I was loading. I discovered that my neck tension was not as consistant as I thought and made some changes in my case prep and sizing proceedures to help resolve the problem.
Re: Neck Tension vs Concentricity
I wasn't trying to imply that I had any neck tension problems, was just wondering if there is a correlation between neck tension and concentricity. Bullet seating pressure seems to be consistent. I simply have never neck turned any of my Lapua brass.
Also, I always anneal my cases after two firings.
I wasn't trying to imply that I had any neck tension problems, was just wondering if there is a correlation between neck tension and concentricity. Bullet seating pressure seems to be consistent. I simply have never neck turned any of my Lapua brass.
Also, I always anneal my cases after two firings.
Re: Neck Tension vs Concentricity
I missed the annealing. I always neck turn new cases, Lapua, WW, Remmy.... The last batch of 260 Rem Lapua cases had neck wall thicknesses that varied from 0.015" to as much as 0.017" in the same case. Most were better, but out of 200 very few had under 0.0005" variation. The variation alone will cause some run-out.
OFG
I missed the annealing. I always neck turn new cases, Lapua, WW, Remmy.... The last batch of 260 Rem Lapua cases had neck wall thicknesses that varied from 0.015" to as much as 0.017" in the same case. Most were better, but out of 200 very few had under 0.0005" variation. The variation alone will cause some run-out.
OFG
Re: Neck Tension vs Concentricity
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: oldfatguy</div><div class="ubbcode-body">After 5 firings it is time to anneal your case necks.
OFG </div></div>
OFG,
I had between 20-30 reloads on my last batch of 500 old R&P cases. This was the last batch of R&P cases I purchased over 30 years ago and they were doing very well without annealing. I recently chose to retire them all as I was finding increasing numbers of cases with micro cracks at the case mouths during my routine post cleaning/pre-loading inspections. These .308Win cases were all loaded using modest loads between 2,600-2,700fps out of a 24" barrel depending on bullet weight.
HTH!
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: oldfatguy</div><div class="ubbcode-body">After 5 firings it is time to anneal your case necks.
OFG </div></div>
OFG,
I had between 20-30 reloads on my last batch of 500 old R&P cases. This was the last batch of R&P cases I purchased over 30 years ago and they were doing very well without annealing. I recently chose to retire them all as I was finding increasing numbers of cases with micro cracks at the case mouths during my routine post cleaning/pre-loading inspections. These .308Win cases were all loaded using modest loads between 2,600-2,700fps out of a 24" barrel depending on bullet weight.
HTH!
Re: Neck Tension vs Concentricity
If you're running a lot of neck tension then variations in neck tension can affect seating depth. The bullet will deform at the point of contact with the seating die. This varies with bullet style,mfg, seating die stem shape and neck tension. I like bushing dies so I can control neck tension. I like something in the middle of the road for neck tension. Too much and bad things happen. I also take my favorite bullet and use it to lap the stem to increase the surface area that contacts the bullet.
If you're running a lot of neck tension then variations in neck tension can affect seating depth. The bullet will deform at the point of contact with the seating die. This varies with bullet style,mfg, seating die stem shape and neck tension. I like bushing dies so I can control neck tension. I like something in the middle of the road for neck tension. Too much and bad things happen. I also take my favorite bullet and use it to lap the stem to increase the surface area that contacts the bullet.
Re: Neck Tension vs Concentricity
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: YAOG</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: oldfatguy</div><div class="ubbcode-body">After 5 firings it is time to anneal your case necks.
OFG </div></div>
OFG,
I had between 20-30 reloads on my last batch of 500 old R&P cases. This was the last batch of R&P cases I purchased over 30 years ago and <span style="color: #FF0000">they were doing very well without annealing.</span> I recently chose to retire them all as I was finding increasing numbers of cases with micro cracks at the case mouths during my routine post cleaning/pre-loading inspections. These .308Win cases were all loaded using modest loads between 2,600-2,700fps out of a 24" barrel depending on bullet weight.
HTH!
</div></div>
Twenty to thirty firings is pretty good case life. Annealing is something that one can do but isn't required. Just like neck turning, flash hole deburring, weight sorting, ultra sonic cleaning, and such.
Bare minimum is that the loaded round chamber and fire. Beyond that there are lots of "busy work" activities that retired people with lots of spare time can do.
OFG
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: YAOG</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: oldfatguy</div><div class="ubbcode-body">After 5 firings it is time to anneal your case necks.
OFG </div></div>
OFG,
I had between 20-30 reloads on my last batch of 500 old R&P cases. This was the last batch of R&P cases I purchased over 30 years ago and <span style="color: #FF0000">they were doing very well without annealing.</span> I recently chose to retire them all as I was finding increasing numbers of cases with micro cracks at the case mouths during my routine post cleaning/pre-loading inspections. These .308Win cases were all loaded using modest loads between 2,600-2,700fps out of a 24" barrel depending on bullet weight.
HTH!
</div></div>
Twenty to thirty firings is pretty good case life. Annealing is something that one can do but isn't required. Just like neck turning, flash hole deburring, weight sorting, ultra sonic cleaning, and such.
Bare minimum is that the loaded round chamber and fire. Beyond that there are lots of "busy work" activities that retired people with lots of spare time can do.
OFG
