Concentricity , what seater die should I get ?

[Metal god]

This will be for 308 but will be needing one in 223 as well at some point .

I just bought the Sinclair concentricity gauge https://www.brownells.com/reloading/...prod37479.aspx

Just been playing around with it but it seems to show my FL sizing does pretty good with the worst my necks are off are .0015 . That's likely the neck wall thickness variance because I use the expander button . So my guess is my case prep is fine since I don't turn my necks and I seem to have fairly concentric necks .

My bullets are anywhere from .003 to .006 depending on the loading components . I say components because although both my LC-14 and LC-12-lr cases only have .0015 neck run out . when using the same bullets the LC-14 cases have .005 runout while the LC-12-lr only have .0025 .

Maybe this is normal but seems odd to me . Case prep is pretty much the same regardless of what I'm prepping so what's causing the LC-14 brass to allow the bullet to have more run out then others ?

Any tips and or hints to help use and understand the gauge would be appreciated .

I'm assuming since my cases are sized pretty consistently . The problem is my seater die . I use the standard Redding seater die with the after market micrometer stem insert .

https://www.midwayusa.com/product/10...ing-seater-die
https://www.midwayusa.com/product/10...ing-micrometer

Although pretty cool and doo seem to work pretty well . I may be willing to step up in quality and precision . Obviously the Redding competition seater die is the front runner . How ever I run a few compressed loads ( less in 308 then 223 ) but still do in both . I've read that the Redding seater stem or what ever it's called is on a spring and compressed load can result in inconsistent seating depths ?????

So my next choice is the Forster seating die https://www.midwayusa.com/product/39...ter-seater-die
Only because I've heard it does better with compressed loads ?????

If there's something else you recommend , please do and I'll consider it .

Thanks Metal

[hounddawg]

if you going to go down a rabbit hole might as well take a flying leap

http://www.xxicsi.com/calibrated-bullet-seater.html

and a http://www.xxicsi.com/hydro-bullet-seater.html

[brasscollector]

I'm not using anything nicer than what you're using and I'm getting about the same results. I have the cheap Redding FL 308 sizing die (with an expander, Oh No!) and standard seating die and I'm usually at or under .005" runout on my LC13/14 reloads. I'm seating hornady 150 FMJBTs, so not even a 'match' grade bullet, although I think they do pretty good regardless.
Not trying to come off as snarky or sarcastic but how would you feel about spending almost $300 and getting the same results?

[hounddawg]

Not trying to come off as snarky or sarcastic but how would you feel about spending almost $300 and getting the same results?

but it is scientific fact that the more $$$$ you spend on reloading equipment and the slower it operates the more accurate the ammo....right? I read that on the internet so it has to be true

[Unclenick]

0.005" runout is still enough to cause measurable dispersion on the target. 0.0015" is getting down in the noise, though.

If you are getting good results with the standard seater, just stay there. My 30-06 Redding standard seater didn't do nearly as well, allowing up to 0.008" TIR which can cause up to about one moa of dispersion with some bullets in that chambering. To be fair, this was decades ago and I was using an inadequate press at the time (Lyman Spartan turret). Nonetheless, going to the Redding Competition Seating die cut that down to about 0.001" average, with an occasional 0.002" due to a case with very uneven neck wall thickness.

Since then, I've found the Lyman M-die, when set up to only put the little step in the case mouth and not to flare it, will let you start a bullet straight into a conventional seating die by allowing it to sit squarely in the case mouth before you start the round up into the seating die (no more hanging on with your fingers until enough of the bullet has disappeared up into the die body). This provides the straight start and seems to do very well and cost a lot less to get into.

The spring in the Redding Competition Seating Die returns the case alignment sleeve that follows the case body. It is not between the stem and the micrometer stop, so there is no problem there. Only if you compressed so much that it bulged the case inside the alignment sleeve could I see the potential for an issue to arise.

[RC20]

I use the RCBS comp dies but I don't know if they are any more precise than the regualr (different color)

I like them because of the bullet seater setup you get with the dies.

My brother got me into M die and per Unclenick , that is my method as well, I have removed the expander plug from my sizing dies.

[disseminator]

I also have the Sinclair Concentricity Gage and I am very happy with it. About the only bad thing I can say about it is that it leaves little traces on the brass where the rollers ride. Not a big deal to me.

As for which seater you should use, I recommend and use the Forster Comp Seater. It's as good as the Redding, maybe better if you consider that it's ok for compressed loads, and it's at least $50 less on average. That savings allows you to buy the Forster sizing die as well which is also excellent.

I am not an expert reloader. I've read that a max of .003" runout is desirable for precision shooting so I decided to try and match that level for my hunting rounds. With brass sorting, preparation, and good reloading practices, I have been able to get my runout down to .002" in my 308 and 280 hunting loads using Federal Trophy Bonded Bullets.

I think the brass sorting and weighing was a really big factor. You gotta keep and eye on the case necks too.

The deal was sealed when I switched from my Redding Big Boss II and bought a Co-ax press. I was getting .004"-.006" on the Big Boss II even with the Comp Seater.

[Metal god]

if you going to go down a rabbit hole might as well take a flying leap

Thanks for the link , I bought one xxicsi for every caliber and bullet I shoot NOT !!! They do look very cool though . When I win the lottery those will be on the short list .

how would you feel about spending almost $300 and getting the same results?

Not good and is why I'm asking here . Needs some pointers on why with all other things being equal one of my loads has much worse runout then the other or really the rest . To be honest , I've had issues with these LC-14 cases from the get go . I'm inclined to assume this is just another thing they don't do well .

0.005" runout is still enough to cause measurable dispersion on the target. 0.015" is getting down in the noise, though.

I assume you meant .0015 and not .015 ?

If you are getting good results with the standard seater, just stay there

Well I actually on the whole have not been to unhappy with my results to date . Although I've not seen a 1/4 moa group in quite some time . I didn't shoot them all the time but they were seen at the range from time to time . Nothings really changed except throat erosion and I figured that's been why ?

Since then, I've found the Lyman M-die, when set up to only put the little step in the case mouth and not to flare it, will let you start a bullet straight into a conventional seating die by allowing it to sit squarely in the case mouth before you start the round up into the seating die (no more hanging on with your fingers until enough of the bullet has disappeared up into the die body).

I seen you talk about the M-die often but never felt the need and there's been very few things over the years you.ve suggested that I have not tried . It just that I shoot boat tail bullets almost exclusively and I don't need to hold then with my fingers even a little bit . I just set them on top of the case and they stay there .

I've even found that it does not matter even if the bullet is really crooked . I tested this and if I go slow my seater stem straightens them out better then I could ever do by hand . What I do is slowly raise the ram to where I barely feel the pressure of the bullet engage the seater stem then back out just a tad then seat the bullet . If I were to back out all the way the bullet is always sitting straighter then I could do by hand .

EXAMPLE OF THAT BELOW




That second pic is the bullet just sitting on top , it is not seated at all and I can lift it right off the case . The seating stem just straightened it up .

The spring in the Redding Competition Seating Die returns the case alignment sleeve that follows the case body. It is not between the stem and the micrometer stop, so there is no problem there. Only if you compressed so much that it bulged the case inside the alignment sleeve could I see the potential for an issue to arise.

Interesting , I was under the impression that the stem it self was floating and did have some sort of heavy spring between it and the micrometer . To date I've never had a compressed load that bulged the case but I have had them stop being seated to the depth intended . I usually come across this during load development . It happens when each charge is more then the last and filling the case more and more at each increment . I've seen my COAL slowly grow by a few thousandths every .3 to .5gr increment I go up depending on the cartridge I'm loading .

This only happens when I'm not using a drop tube and just dumping the charge into the case with a small funnel . If this starts happening I'll tap the edge of the head on the bench to get the powder to settle so I can seat the bullet that extra little bit . I don't like doing this because I'm always afraid me forcing the powder to settle will cause that charge to burn and or ignite differently then those ones that did not need it .

I do like the M-die for handgun loads because I'm always shooting flat based bullets there but have not tried it yet .

I use the RCBS comp dies but I don't know if they are any more precise than the regualr

If those are the ones with the window area you insert the bullet on the side from . They scare me because I have big fat fingers and the thought of the control needed to work those makes me shy away from those and the fact as the above pics show just setting the bullet on the case for me works just fine .

As for which seater you should use, I recommend and use the Forster Comp Seater.

Which is what the plan is/was until UN pointed out the Redding seater die can be used on compressed loads . So now the question is , is the Redding die $50 better ? Midway has the Redding die right now for $132 , It seems not to lng ago I remember them only costing around $110 . That $20 just is one of the reasons I started this thread . $50 difference is pretty big IMO , If the Forster is going to do the same thing I'd rather buy more bullets

I'm also not apposed to getting a better single stage press although I do like the Hornady bushing system . This Hornady press is not all that stiff and the linkage and ram have a lot of play in then . I would not be surprised the press it self is the cause of all the runout issues .

[Unclenick]

Originally Posted by Metal god

I assume you meant .0015 and not .015 ?

Yuppers. I went back and fixed the original. Bloody fat fingers missing key hits!

Originally Posted by Metal god

I've even found that it does not matter even if the bullet is really crooked

Boy, that's sure contrary to my own findings. When I got my Dillon Square Deal B for loading all my 45 Auto match loads back around 1990, I quickly noticed a lot of rounds showed an exaggerated mirroring of the location of the base of the bullet on one side of a case and not the other, indicating bullet tilt. So I chucked the Dillon powder drop/operating tube in my lathe and ground the profile to match the Lyman M profile. With the bullets sitting upright and straight, they seated straight and the mirrored base position thereafter showed all the way around on every cartridge, signifying significantly reduced bullet tilt. Sandbagged 1911 Goldcup groups (5-shot) got down as tight as 0.37" CTC at 25 yards! I've been a fan ever since.

Originally Posted by Metal god

Nothings really changed except throat erosion and I figured that's been why ?

Maybe not. This is remarkably easy to test. Use your runout gauge to identify which side of each cartridge is high. Use a Sharpie to mark the rim at the high side (or low; doesn't matter which, as long as you are consistent once you start), then shoot a 30-shot group with the high side all at the same side of the chamber and another with the high side rotated 90° for each successive shot. If the first group is substantially (25% or more) smaller than the second group, you have an issue to address and will benefit from reducing runout.

Originally Posted by Metal god

I was under the impression that the stem itself was floating and did have some sort of heavy spring between it and the micrometer.

It is floating, but without a separate spring. What is confusing is the spring acts on the assembly that includes the stem, but the back end of the stem stops hard on the micrometer spindle nose. Floating, in this context, just means free to slip laterally (left, right, forward, backward) in order to self-center over the bullet, evenly centering contact with its ogive. There is no laterally directed spring—just the longitudinally directed one for the sleeve chase.

Originally Posted by disseminator

As for which seater you should use, I recommend and use the Forster Comp Seater. It's as good as the Redding, maybe better

The Forster is the previous incarnation. The Forster sliding sleeve patent was in force from 1969 to 1989 and the license sold twice in that time period, ending up at Forster. The Redding patent was in force from 1989 to 2009. What Redding did was take the expired Forster patent and add the floating seating stem. If you go to USPTO.gov and look up the Redding patent, what you find they claim is the floating seating stem in combination with the sliding sleve and they describe a scenario in which the floating stem corrects for one aspect of bullet tilt that the older Forster design does not address. How often this comes up in real life, I have no idea, as I know prople who swear by both designs. This article shows, with targets, what using the Redding seater can get for you, but does not include the Forster in the comparative test. I've never seen an actual head-to-head comparison with the Forster version published. The Redding dies were $49 ($45 on sale) when I got my first one (30-06) circa 1990.

Originally Posted by Metal god

To date I've never had a compressed load that bulged the case but I have had them stop being seated to the depth intended .

That is likely elasticity of the powder pushing back on the bullet like a spring, assisted by the air compressed in the case. The only ways I know to address that are to use a L-O-N-G drop tube prior to seating, and leaving the press ram up for a few seconds to let air pressure equalize a little and the round settle. I have a 4 foot drop tube I have used on occasion.

Originally Posted by Metal god

I'm also not apposed to getting a better single stage press

Here is where Forster really shines. Take a deep breath and shell out for their Co-ax press. You'll never look back.

[Metal god]

Thanks Unclenick , good info as always

Boy, that's sure contrary to my own findings. When I got my Dillon Square Deal B for loading all my 45 Auto match loads back around 1990

I should have been more clear . I was only speaking to rifle loads using boat tail bullets . Oh man did I have issues when I first started loading handgun cartridges like the 45acp . There were times although not literally the bullet seem to go in sideways . Not really but one side of the case would clearly be bulged with the clear bullet base outline appearing in the case .

I still very much need to pay close attention to bullet alignment when loading handgun cartridges but most of my rifle bullets align them selves pretty much .

[hounddawg]

I was half joking about the arbor press Metal God but on the serious side I am seating my .260 match ammo using a Forster .308 micro adjust seating die.

My runout must be through the roof !!!! Not actually. I just checked 15 roundS I loaded for a test and out of fifteen checked two had a runout of .0015 the rest were less than .001.

A good sizing sizing die was the key to low runout for me. If that neck comes out of the sizing die concentric that little bullet is not going to bend it without shaving some of the copper jacket off. If you see copper shavings at the neck after seating, you have a seating die issue, if there are no shavings you have a sizing die issue

[jmorris]

I start by checking a fired case, then check again at every step, just so I know what’s going on. Also try just the size die, no expander, different lubes and methods of application, etc.

This also doesn’t stop once I have a loaded round either. Once I made a couple of tools to get a quantitative value for runout I was surprised to find that a batch of ammunition that had proven to be quite accurate had a generous amount of runout. I couldn’t greatly figure out why it shot so well until I chambered a few of them then retested them to find that once chambered, they straightened out.

Further off the lands would make this less likely but you don’t know until you go through the steps.

[RC20]

As for the RCBS vs say the Forrester seaters, I have two of the RCBS and one of the Forester. Forester is limited to 30-06 and I can use the the RCBS on both (with the extender shell holder)

For me the Foresters is harder to seat because I have to get my (also fat) fingers on the bullet then seat it in the shelf and get it in between the sleeve and the mouth of the case.

The RCBS just drops in.

I may not be good enough shooter to see any difference.

I do know that my most recent steller group (by my standards) came out of the RCBS in a barrel that has defied a consistent good load (got 1/4 inch 5 shot out of it - it likes the Hornady 168 ELD)

To me they seem some and some, I don't worry about concentric as I am not going to shoot 1s or 2s.

Sizer wise the Forster seems to work fine, thought it might be a bit better for the longer 30-06.

First thing I did was break the stem as its a floating de-primer and I had a couple of milgary rounds mixed in with my RP. The crimps were removed but had a trace left. Forester does not even tolerate a hair.

RCBS does and they replace parts even if you do something dumb. Forrester does not.

Needless to say, Forester is not high on my list. Redding? Expensive and you have to add the micrometer to their seaters. hmmm.

[hounddawg]

I like the RCBS for the same reason RC20

I just don't see how the seating dies could bend a neck out of concentricty.

Think about it. I have a .015 (appx) thick ring of brass whose inside diameter is .003 (my bushing) smaller than the bullet diameter and the bullet is going in least .2 inches into that ring. The tip of the bullet is free floating in the cone of the seating stem

That bullet will follow the path of least resistance which means following the inside of the neck. It would take a considerable amount of force to force the neck to bend out of alignment with the case.

I run a Wilson inside neck reamer through my necks every 5 or so firings and the inside of the necks will show some high spots in the brass thickness that have been shaven off afterwards. I can imagine the uneven brass cocking the bullet slightly in the neck

[T. O'Heir]

"...EXAMPLE OF THAT BELOW..." That case mouth appears to not be chamfered. Doing that alone will help. Don't over complicate the whole process. Which is what most of the assorted gadgets do.

[F. Guffey]

. I would not be surprised the press it self is the cause of all the runout issues .

Good luck with that, reloaders are under the allusion the Rock Chucker is a cam over press. Time after time after time I have said the Rock Chucker is not a cam over press and I have insisted the press linkage gets tangled up when the ram is raised. When the linkage goes into a bind the ram is shoved back at the bottom and forward at the top. And I have insisted the only thing that aligns the ram/shell holder with the die is the case. Without a case in the shell holder the ram/shell holder really gets crooked.

F. Guffey

[Metal god]

I just don't see how the seating dies could bend a neck out of concentricty.

I just did a quick test that was interesting . I took 2 LC-10 cases the had a neck run out of more then .001 but less then .0015 and seated a 168gr BTHP just barely into the neck . If I had to guess maybe .010 to .015 deep I then tested the runout on both bullets just ahead of the case mouth . They both were about .0015 . I then seated them both the rest of the way to a COAL of 2.820 then test the bullets again just ahead of the case mouth . One stayed about the same while the others runout grew to .0025 .

I did it with a case that had a neck run out of .002 and the bullet had less runout then the neck at both seating depths . Yes this is very limited in numbers but when the first two or three of any test shows an issue I tend to believe it ain't getting better with more volume although I understand it could .

So now you have to wonder where that movement is coming from . Is it the extra push of the seater stem pushing the bullet out of alignment ? Maybe the outside diameter of the necks are actually more concentric then the insides ? Maybe there's a small abnormality on the inside of some of the necks the causes the bullet to get crooked the further it is seated . I don't know , the list of things that could cause that seems to go on if you really think about it .

As for the RCBS seater die , just dropping it into that hole sounds like something I could do .

Now the question is which of these can seat both regular 175gr smk and the uber long nosed Beger VLD's with out needing an insert change ? I just bought some Berger 200.20X Hybrid bullets that have a very long nose . I hade to drill out my Redding seater stem to allow my seating die to seat hem off the side of the bullet rather then the tip .

[Unclenick]

There are two sources of bullet tilt being discussed. One source is a tilted neck on a case that guides a seating bullet in at an angle. The other is a seating die that does not straighten alignment of the bullet with the neck before pushing it into the case, so it goes in at an angle even it the neck was straight.

If you follow my link to the article on the Redding seater, you will find it mentions that the Redding was the only seating die that actually could produce runout lower than the neck runout, though not be a lot. Consider a die that constrains the sides of the case body and constrains alignment of the bullet to be coaxial with the case body as it seats, the only thing free to give way in that scenario is the neck. It won't be perfect and the neck is a little springy, but that's how it works.


MG,

My example of the first time I saw bullet tilt affect accuracy was not meant to suggest it is in any way a principle unique to handguns. It was mainly to illustrate seating tilt, even in a neck that was straight, can be significant and that the Lyman M type expanding profile, which many folks now use on rifle cartridges, will correct it.

A. A. Abbatiello measured the effect of bullet tilt in testing samples from 42 lots of National Match ammunition and showed a little over an MOA of dispersion could be caused by it in the 30-06 with the BT FMJ M. His results matched his mathematical prediction of the effect. But he also marked the high side and found that if the high side of the excentric bullet is always inserted on the same side of the chamber, the dispersion was cut in half. That's why I suggested the experiment. 30 rounds each gives you solid statistical certainty, but Harold Vaughn showed it using a one-holer integral machine rest rifle. He produced the same 0.004" of tilt in 8 rounds intentionally, rotating the high side of the bullet tilt 90° for each shot and got four distinct POI locations as a result, and then repeated, putting the second bullet in the same hole for each of the four POI locations. So you can do it with a smaller number of rounds if you can shoot very tightly. If you looked at the targets fired for the article I linked to, you can also see the effect at work there.

If you have 0.0010" to 0.0015" total indicated runout, your seating die is handling straightening pretty well. My original Redding standard seating die would not do that. I don't know if they changed the shape of the seating die since 1990 or not. If, as an experiment, however, you use a Lyman M die to form a step in the cases and then seat your bullets with a standard RCBS seating die after placing them upright in the step, they will be just as good. It takes an additional step, but it is nonetheless an example of another way to skin the cat.

Conventional wisdom holds that if the neck is bent, no seating die will straighten it any. The article I linked to shows the Redding Competition Seating Die actually can straighten it a little, where no other seating die in the test could at all. This is because the case body and bullet are held rigidly in coaxial alignment during seating, so the only place free to give any when lateral offset forces exist is the neck of the case. The Forster may do the same thing, but I don't have one to check. There is still spring in the brass, so the effect is small, but it seems to help a bit. Nonetheless, starting with perfectly coaxial case neck and body is the only way to approach perfection. Neck reaming and outside turning to achieve smooth, uniform wall thickness improves coaxiality and bullet centering further, assuming your gun can shoot tightly enough to tell the difference.


P.S. I was editing when the last three posts went up. That's interesting about the round whose runout increased. Off-axis seating force had to be involved unless the case wall thickness runout increases near the neck. You could measure that. Meanwhile, I think you've identified the advantage of the sliding sleeve seating die designs. They keep the case and bullet aligned.

[hounddawg]

On the press flex thing. Lets think about this a minute. When that case is jammed in that sizing die from web to neck and being hugged by a half inch of steel with the base is being held in a shellholder that has 1/16 of an inch of lateral float built how can you bend that neck unless you bend the entire die.

[Metal god]

On the press flex thing. Lets think about this a minute. When that case is jammed in that sizing die from web to neck and being hugged by a half inch of steel with the base is being held in a shellholder that has 1/16 of an inch of lateral float built how can you bend that neck unless you bend the entire die.

Are you responding to Guffey or T-Oheir ? I don't see there posts so I have no idea why we are now talking about the neck being bent during sizing . I'm not sure what sizing has to do with this . I'm already past that part of the process when looking for case/neck concentricity or seating the bullet so that's moot as it relates to this thread .

Either way I pulled the trigger on the Redding competition seating die . Found one online for $110 shipped , Hmm I never looked to be sure it was new , hope it's not used

EDIT : Just called the store , It's a new product . I told them I was asking because it's such a good price . They were surprised I was asking and wanted to know where I saw it for more so they could search and be sure we were comparing apples to apples , we were .

Looks like I'll need a VLD stem though . Looks like they have standard and long choices . Any idea which I should get ?

[hounddawg]

Sorry MetalGod somehow press flex got mixed in with concentricity earlier in the thread and I was replying to that.

But you have got me to wondering if you had a neck with uneven inside thickness would it cause runout on the bullet even if the neck itself was concentric. I don't get much runout anymore but I do a whole lot of case prep

Grats on the Redding, never used one of their seaters but if they are as good as their sizing dies you will have a winner

[cw308]

The combination that works for me is the standard RCBS F/L die , Redding Competition shellholder set of 5 for sizing and the Redding Competition Seating die for seating. Tried bushing dies , neck sizing , runout was horrible untill I went back to full sizing , runout averaged .001k, groups are tight and consistent.

[Metal god]

Sorry MetalGod somehow press flex got mixed in with concentricity earlier in the thread and I was replying to that.

I remember that now and is why I brought up the new press possibility . I agree with you that the sizing process locks everything in place and not likely going to bend the necks . How ever I've pulled my expander ball though a few none lubed necks that took quite a bit of force to pull it though . I'd think that feeling I felt could easily pull the neck out of alignment but that would be seen when testing the neck concentricity after sizing . Right now the few I've tested so far are pretty good so I don't think that's the issue for me although it could be for someone else .

cw308 , I was hoping you'd chime in . I knew you work with these products but did not remember the specifics other then you switching back to a standard FL-sizing die .


I went and measured my tip to ogive distance on a 175gr smk and the new Berger 200,20x bullets . The 175's are .662-ish long while the Berger 200.20x bullets are .844-ish . Almost 2 tenths seems way longer from tip to ogive o me .

[cw308]

Metal God
Thanks , lm always in , reading everything I can on reloading , if I can add to the conversation and possibly help I will . Today I had one of those a_ _ h_ _ e moments , cleaned the die and didn't adjust the expander shaft with the expander ball except for the pin .as I sized I blew out the primer pocket from the web , that was a first .The pin isn't attached , I decap first . I'm going to swap out the stem assembly from the neck die just to be safe . Can't stop kicking myself in the ass. Be Well.

Chris

[hounddawg]

Pull the expander button off and toss it in a drawer where it can do no harm. That will solve part of the problem right there. Depin with a universal also