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Setting neck tension….

250shooter

Private
Minuteman
Feb 6, 2018
96
6
35
West Texas
Wanting to get a my neck tension a little better. Using a Redding full length bushing die with same lot Lapua brass. Would running expander help? I’ve never used an expander so trying to figure out when and if I should incorporate it into my process. Any help appreciated.
 
I use the Redding Type S almost exclusively on all my rifle dies. Took out all the expander ball and run it through the mandrel as my last step on the sizing process. It's extra work but in my mind produces better ammo.
 
Taking out the expander ball and using a mandrel isn't more consistent than using the expander ball alone. The merits of using expander mandrels don't include improved neck ID consistency. OP should probably start by explaining what inconsistency he is experiencing because just blindly changing his process likely won't change anything but the weight of his wallet.
 
I’m not getting a constant tension. I don’t have exact numbers I’m not using an arbor press. But seating some bullets is much easier than others. Which throws off my seating depth from case to case
 
Wanting to get a my neck tension a little better. Using a Redding full length bushing die with same lot Lapua brass. Would running expander help? I’ve never used an expander so trying to figure out when and if I should incorporate it into my process. Any help appreciated.
In terms of "neck tension" an expander mandrel really doesn't offer much improvement with consistency. If you want improvement the consistency of your neck tension, you need to anneal your brass. Inconsistent neck tension is typically due to variation in the neck's hardness. But, using ann expander mandrel instead of the expander button does give you more control of the amount of neck tension you might want to play with.

What an expander mandrel really offers over an expander button is a reduction in the neck's runout and with annealing you get more consistency there too.
 
I’m not getting a constant tension. I don’t have exact numbers I’m not using an arbor press. But seating some bullets is much easier than others. Which throws off my seating depth from case to case

Stop using the word "tension", unless you can measure your brass hardness you have no idea what the tension is. Inconsistent seating pressure can be cause by many different things; chamfer, hardness, ID variation, neck shoulder junction donuts, etc. Start by describing exactly what is causing the seating pressure inconsistency.

Everyone on the internet just recommends to do what they do even when they don't know why they do it.
 
In terms of "neck tension" an expander mandrel really doesn't offer much improvement with consistency. If you want improvement the consistency of your neck tension, you need to anneal your brass. Inconsistent neck tension is typically due to variation in the neck's hardness. But, using ann expander mandrel instead of the expander button does give you more control of the amount of neck tension you might want to play with.

What an expander mandrel really offers over an expander button is a reduction in the neck's runout and with annealing you get more consistency there too.
I do anneal my brass
 
my happiest day in reloading other than not blowing my self up was realizing I did not need to buy any more neck bushings ( shame that epiphany happened after buying 6 of the darn things none were the correct size all allowed a bullet to just slip inside the case ) I just use the empty dye body I have with the insides taken out it closes the neck how tight is unimportant (but it's tight enough to hold a bullet ) after I open it with the expanding mandrels and set it to what I am looking for it's good to go . best of luck to you which ever way you do it .
 
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Stop using the word "tension", unless you can measure your brass hardness you have no idea what the tension is. Inconsistent seating pressure can be cause by many different things; chamfer, hardness, ID variation, neck shoulder junction donuts, etc. Start by describing exactly what is causing the seating pressure inconsistency.

Everyone on the internet just recommends to do what they do even when they don't know why they do it.
Ok bro thanks for the info. And if I knew what was causing the issue I would have explained it obviously. It’s why I posted the post in the first place.
 
Stop using the word "tension", unless you can measure your brass hardness you have no idea what the tension is. Inconsistent seating pressure can be cause by many different things; chamfer, hardness, ID variation, neck shoulder junction donuts, etc. Start by describing exactly what is causing the seating pressure inconsistency.

Everyone on the internet just recommends to do what they do even when they don't know why they do it.
While you're right about the word "tension", I'm sure you know what he's referring to and you might try to help rather than confuse??? I doubt you're going to be able to change the way the reloading community uses that word, huh? 🥴 🤷‍♂️
 
While you're right about the word "tension", I'm sure you know what he's referring to and you might try to help rather than confuse??? I doubt you're going to be able to change the way the reloading community uses that word, huh? 🥴 🤷‍♂️

I don't know what he is referring to and neither does he. If he has inconsistent neck ID then he needs to say so. A mandrel won't solve it either.
 
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I do anneal my brass
That's good, IMHO. Just be sure you're annealing process is actually getting the job done. Often, when one is annealing and still getting a lot of inconsistencies in the neck and shoulder bump, it's because the annealing isn't really happening. If you're annealing is working, your neck "tension" (as the word is commonly used) should be consistent.
 
If you are not lubing before seating each bullet it could be as simple as friction . Do you give them a good brushing after annealing to remove burnt on crud inside ?
 
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A lot of guys get great results running a Redding type S bushing die. Sizing the neck .003” below desired tension. Then opening with a mandrel to bring the tension to about .0015”

My preference is Lee collet die/Redding body die combo. I do anneal every firing. Neck tension .0015”.

Those are the two I recommend. With annealing. I always trim/chamfer/deburr/brush inside of neck as well
 
I’m not getting a constant tension. I don’t have exact numbers I’m not using an arbor press. But seating some bullets is much easier than others. Which throws off my seating depth from case to case

That’s because you have variance in neck thickness. The thicker necks size down to a smaller ID and result in harder bullet seating. The thinner necks size down to a larger ID and result in easier bullet seating. The solution is neck turning, or a smaller bushing followed by expanding with a mandrel.
 
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That’s because you have variance in neck thickness. The thicker necks size down to a smaller ID and result in harder bullet seating. The thinner necks size down to a larger ID and result in easier bullet seating. The solution is neck turning, or a smaller bushing followed by expanding with a mandrel.
That's a good point about the neck thickness. It's not unusual for Lapua to have a .001 variance in the thickness of the neck (how much can depend on the caliber). Using a sizing die with an expander ball tends to mitigate this issue a little. Certainly when using an expanding mandrel, one is moving the variations from the inside diameter to the outside diameter where it can show up prominently, where neck turning pretty much eliminates this issue.
 
I don't know what he is referring to and neither does he. If he has inconsistent neck ID then he needs to say so. A mandrel won't solve it either

Stop using the word "tension", unless you can measure your brass hardness you have no idea what the tension is. Inconsistent seating pressure can be cause by many different things; chamfer, hardness, ID variation, neck shoulder junction donuts, etc. Start by describing exactly what is causing the seating pressure inconsistency.

Everyone on the internet just recommends to do what they do even when they don't know why they do it.
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This post only proves the point that “tension” shouldn’t be used to refer to the inside diameter or interference fit.

In most any other thing we don’t just say “we all know what they mean” even though it’s completely wrong. We’d guide them and fix the issue.



On the topic at hand, everyone is giving an answer that is a portion of the entire equation.

I’d suggest the OP do a deep dive on here and accurate shooter and really learn what goes into what’s actually involved in neck tension. Including but not completely limited to:

-Interference fit
-Brass thickness
-Brass hardness
-Friction

Also chamfer and such. But chamfering matters far, far less than people think. Another good thing the AMP press has provided.
 
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Ok bro thanks for the info. And if I knew what was causing the issue I would have explained it obviously. It’s why I posted the post in the first place.
I find that the most variation in neck tension I find is when I seat a bullet into an un-annealed case on the odd occasion.
I anneal all my brass, new or old before prepping but, the odd one escapes now & again. This leads to the question of how you anneal & if your brass is in mixed firing lots.
If some cases are getting significantly hotter than others during the annealing process or, some cases aren't getting hot enough, this could definitely cause the issues you speak of.
It may not be the entire cause but, it's a place to start.
 
I see the mandrel not as the only step to success. I see it as a real improvement over dragging the “ball” upstroke with no control over the result ID and possibly affecting HS consistently. And some other stuff I probably do not understand.
 
I've gotten very good results with a redding bushing die and elliptical expander, not using a mandrel. This is with brass that's been fired a few times and anealed properly every firing though. I've found that polishing my elliptical expander helps too. I end up with about .0015 ish smaller case mouth than my bullet.


I understand " neck tension" isn't the correct name to describe how much smaller the case mouth is than the bullet, but what is the correct yet simple way of expressing this idea????
 
I've gotten very good results with a redding bushing die and elliptical expander, not using a mandrel. This is with brass that's been fired a few times and anealed properly every firing though. I've found that polishing my elliptical expander helps too. I end up with about .0015 ish smaller case mouth than my bullet.


I understand "seating tension" isn't the correct name to describe how much smaller the case mouth is than the bullet, but what is the correct yet simple way of expressing this idea????
Hoop tension governs seating pressure.
 
My preference is Lee collet die/Redding body die combo.

This.

I bump shoulders a thou or two with a redding body die and then follow up with the lee collet die on all of my "precision" rifle brass. It has given me the most consistent and concentric seating out of all methods I have tried.

I also leave the inside of my case necks sooty and don't use any lube for seating.
 
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This.

I bump shoulders a thou or two with a redding body die and then follow up with the lee collet die on all of my "precision" rifle brass. It has given me the most consistent and concentric seating out of all methods I have tried.

I also leave the inside of my case necks sooty and don't use any lube for seating.
This is what I do but I just brush the necks with a nylon brush.
I'm in the process of trying to work out a way of modifying a 243 Win Lee neck collet die to be used for 6 BR.
Lee don't make a 6 BR Collet die. I don't believe they custom manufacture las I heard.
 
This.

I bump shoulders a thou or two with a redding body die and then follow up with the lee collet die on all of my "precision" rifle brass. It has given me the most consistent and concentric seating out of all methods I have tried.

I also leave the inside of my case necks sooty and don't use any lube for seating.
How do you clean lube off after sizing? Are you cleaning at all before hand?

I've been trying to think through my process using the liquid lanolin lube. It's faster than hand applied lube but I get some in the necks and walnut dust sticks like crazy so I end up tumbling for too long. Maybe walnut dust could act as a seating lube?
 
How do you clean lube off after sizing? Are you cleaning at all before hand?

I've been trying to think through my process using the liquid lanolin lube. It's faster than hand applied lube but I get some in the necks and walnut dust sticks like crazy so I end up tumbling for too long. Maybe walnut dust could act as a seating lube?


I clean my brass twice in my process, once at the start after decapping to clean the dust/dirt off and again after body sizing to clean the lube off. I wet tumble for 10 minutes each time, with water and dishsoap, just brass (no pins/bb's).

After the second wash, I neck size. With the lee collet die you don't need to use any lube so everything stays nice and clean. Even for the body die you only lube the case walls/shoulder and leave the neck dry as the body die doesn't size the neck at all.

I hand lube my cases. It does take a bit longer, but I also only use a single stage press and batch my brass so I can size a lot of cases pretty quickly when I'm on a roll, I just watch tv whilst I'm doing it.
 
This is what I do but I just brush the necks with a nylon brush.
I'm in the process of trying to work out a way of modifying a 243 Win Lee neck collet die to be used for 6 BR.
Lee don't make a 6 BR Collet die. I don't believe they custom manufacture las I heard.

I used to brush my necks out too, but stopped a while ago and didn't notice a measurable difference in consistency. I reckon the collet die does a pretty good job of crushing any carbon in the neck into "seating dust".

For your 6br collet die, where there's a will, there's a way. Without having a first hand look and a bit of a measure myself, I won't tell you that removing material off the bottom of the die body and collet will work, but that's what my plan A would be if it was me and it looked like the 6br will physically fit into the bare 243 collet up to the neck. You will also need to shorten the mandrel, whether that is by cutting off the bottom of the mandrel and losing the decap pin flash hole centering, or the top of the mandrel and peening a new step onto it is also another thing to think about.
 
I used to brush my necks out too, but stopped a while ago and didn't notice a measurable difference in consistency. I reckon the collet die does a pretty good job of crushing any carbon in the neck into "seating dust".

For your 6br collet die, where there's a will, there's a way. Without having a first hand look and a bit of a measure myself, I won't tell you that removing material off the bottom of the die body and collet will work, but that's what my plan A would be if it was me and it looked like the 6br will physically fit into the bare 243 collet up to the neck. You will also need to shorten the mandrel, whether that is by cutting off the bottom of the mandrel and losing the decap pin flash hole centering, or the top of the mandrel and peening a new step onto it is also another thing to think about.
It would be easy to simply shorten the die body & the sleave however, the trouble is that the slits in the sleave are at or below the level which needs to be removed. I think I may be able to machine a groove in the sleeve & weld or silver solder a ring to create a new binding base. The other hassle is the length of the neck of the 6 BR as it protrudes through the top of the die when held in position.
Regarding the mandrel, I cut the end off that some time ago. After measuring the tolerance in the primer punch pin in the primer spit hole, it appeared that the amount of movement between the mandrel & the mandrel guide in the top of the die was less than the pin in the spit hole. I shortened the mandrel originally to allow neck sizing & neck size adjustment to a primed case.
 
It would be easy to simply shorten the die body & the sleave however, the trouble is that the slits in the sleave are at or below the level which needs to be removed. I think I may be able to machine a groove in the sleeve & weld or silver solder a ring to create a new binding base. The other hassle is the length of the neck of the 6 BR as it protrudes through the top of the die when held in position.
Regarding the mandrel, I cut the end off that some time ago. After measuring the tolerance in the primer punch pin in the primer spit hole, it appeared that the amount of movement between the mandrel & the mandrel guide in the top of the die was less than the pin in the spit hole. I shortened the mandrel originally to allow neck sizing & neck size adjustment to a primed case.

The die body itself should be useable then with a bit taken off the bottom, but I think with the neck length and slit problem you have mentioned the best thing would be to machine a new collet to match your 6br case, which will be a fairly straight forward operation for a competent machinist.

I would run a chamber reamer into a piece of stock, machine down the O.D. to match the external collet dimensions and slit if it were me.

It will likely cost a few $$ to have this done by a machine shop, but it is not an insurmountable obstacle by any means.
 
what does not kill you only makes you stronger , when you get bucked of a horse get up and eat that horse , you can do it , there is no learning with out a little blood loss , and just do it almost forgot quitters never win and winners never quit . best of luck on your next match .
 
Wanting to get a my neck tension a little better. Using a Redding full length bushing die with same lot Lapua brass. Would running expander help? I’ve never used an expander so trying to figure out when and if I should incorporate it into my process. Any help appreciated.

using expander that fits bushing is the same as mandrell that fits bushing, just 1 step less.
maybe if you have very tight fit for mandrell or expander, I would recommend mandrell and not pulling out expander. maybe...
 
I did not see that the OP was lubing the inside of the case neck for bullet seating. Annealing leaves the inside of the neck very "dry". I have to lightly lube inside the necks after an anneal or I get very inconsistent seating force.
 
I did not see that the OP was lubing the inside of the case neck for bullet seating. Annealing leaves the inside of the neck very "dry". I have to lightly lube inside the necks after an anneal or I get very inconsistent seating force.
The thing that's really thrown me off as of late is Eric Cortina saying that he doesn't clean his brass because 1. He doesn't need to and 2. The carbon in the necks is a natural lube. (He claims it's more consistent than using a brush with graphite too)

He's doing all the things we are doing and in large volume, so what's screwing us to the point of needing lube? I don't think it's annealing.