Should I Jump Into The Arbor Press World? (To Improve Seating Depth Consistency)

[CarlGeorge]

I've looked at some of the previous "Inconsistent Seating Depth" threads and they're not providing a clear picture as to what I should do.

I'm shooting straight .284, Berger 180gr Hybrids; seating with a Redding Competition (Micrometer) die and RCBS Rockchuker press. Extreme spread of CBTO is .003"-.004". I'm finding it very frustrating. I've loaded batches with bullets sorted by BTO - and also with bullets sorted by OAL. Those different bullet sorting methods don't seem to have much impact on seating consistency.

I'm getting the sense the Wilson Micrometer Arbor Press die (with the VLD stem) seats based on bullet profile close to (or at) the ogive. Is that the case? Does the Redding (with VLD stem) seat more based on bullet tip?

Will that ES of .003"-.004" that I'm seeing likely be reduced if I go the Arbor/Wilson route? (If I go this route I'd also get the force pack - and so it appears an incremental benefit of taking the Arbor plunge is having seating force data.)

Input / Experiences?

Thanks!

CG

 

[hambone1971]

Is the seating pressure the same when you seat them?
If not run a expander mandrel in the necks to get the inside dia. all the same.
Expander Mandrels here......

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The tool or Expander mandrel holder is here.....

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Neck tension is very important.
HB

 

[CarlGeorge]

Not sure if seating pressure is consistent or not. Hard to tell with the RC.

I do use a mandrel on the cases prior to seating.

 

[Chiquita]

I could be wrong, but I don't think his issue is the neck tension. If I understood his post, he is has the bullet segregated and even doing so he is still getting 3 to 4 thou run off.

 

[J.d. Popkes]

Whenever I have had that issue it was always something in my case prep. Always something causing inconsistencies in tension. From the chamfer all the way to the bottom if there’s a donut and anything in between. Can vary a little with my press handle consistency even.

certainly not saying that I solved it every time but have caught it and corrected it. Not without wanting to throw things however.

 

[Sandstorm]

I load the 284 Shehane and use a .2835 mandrel prior to seating with the 21st Century
Arbor press and the Wilson seater honed out for the 7 Shehane case.
This combo produces some real low neck tension rounds that work real well for me.
I also Use 6.5x284 Lapua brass necked up and neck turned...
Its just what works for me...YMMV
P.s Annealing every time as well

 

[J.d. Popkes]

I could be wrong, but I don't think his issue is the neck tension. If I understood his post, he is has the bullet segregated and even doing so he is still getting 3 to 4 thou run off.

I guess the point of the bullet could be contacting the stem? Hybrid though.

 

[Ledd Slinger]

I've looked at some of the previous "Inconsistent Seating Depth" threads and they're not providing a clear picture as to what I should do.

I'm shooting straight .284, Berger 180gr Hybrids; seating with a Redding Competition (Micrometer) die and RCBS Rockchuker press. Extreme spread of CBTO is .003"-.004". I'm finding it very frustrating. I've loaded batches with bullets sorted by BTO - and also with bullets sorted by OAL. Those different bullet sorting methods don't seem to have much impact on seating consistency.

I'm getting the sense the Wilson Micrometer Arbor Press die (with the VLD stem) seats based on bullet profile close to (or at) the ogive. Is that the case? Does the Redding (with VLD stem) seat more based on bullet tip?

Will that ES of .003"-.004" that I'm seeing likely be reduced if I go the Arbor/Wilson route? (If I go this route I'd also get the force pack - and so it appears an incremental benefit of taking the Arbor plunge is having seating force data.)

Input / Experiences?

Thanks!

CG

In-line dies with VLD seating stems work very well but I’ve achieved even better consistency with seating depths on a threaded Redding die by drilling out the seating stem then bedding it to the bullets I am using. Then I drill out the top two thirds of the bedding in the stem so it only makes contact on the lower portion of the ogive.

The upper part of the ogive on bullets is a lot more inconsistent than the lower part. It especially makes seating depth erratic when a stem is seating on the upper ogive and not the same angle as the bullet ogive.

Haven’t tried bedding a Wilson VLD stem yet but I probably will because my Wilson seater dies are custom matched to my chambers. Bedding the stem to the bullets I’m using in conjunction with the perfect custom die fit to the case should be about as consistent as it gets.

 

[Dusty Stevens]

If your die’s seating stem is right you will not gain anything by going to an arbor press. If the arbor press die isnt right itll be the same thing. If the stem isnt right follow some of the advice on here and make it right. Usually better consistency with a wilson type die happens because it has a better seating stem not because its a better design

 

[Richard Coody]

Depends on just how far down the rabbit hole you want to go.
Certainly if your seating stem is contacting the point of the bullet that is a problem that needs to be corrected
If the bullets you are using don't have a consistent ogive curve you will have a problem. No amount of sorting will help because the seating stem contacts the ogive at a different point than your comparator.
A loose press or even a different stroke while seating can be a problem. That magic word consistency comes up. That is why an arbor press works so well for many.
Understand many have great results without the following steps.
Then we get to brass prep and consistent neck tension. This is what I learned.
Consistency is the goal.
Annealing done right gives you the same consistent brass at every reloading. Work hardened brass will result in inconsistent neck tension. If you use a lot of neck tension inconsistency doesn't show as much.
Brass prep is the key
One tool that will really teach you what it takes to get consistent neck tension is an arbor press with a force gauge. You will quickly learn if your procedure produces consistent neck tension.
Neck turn for consistent neck thickness. More consistent neck tension and reduces runout.
Find a sizing technique, dies, mandrels, process that produces consistent neck tension. I find that my k&m mandrel kit with mandrels in .0005 increments as a final sizing gives me more consistent neck tension and allows me to find the neck tension my rifle really likes.
Reloading is a learning process. It is also an incremental process. The entire process has to improve together. Doing one step better may not yield the improvement you expect.

 

[Longtrain]

I stuck my head down that rabbit hole. Wilson, nice stuff, didn’t help the problem.

I bought a Sinclair bullet measuring tool to measure my bullets BTO, trying to come up with a perfect way of using the tool to get consistent measurements was frustrating to say. Measure one bullet, remeasure, you get a few thousandths variation. Try again, still off .002. You spend 3 minutes trying to measure one bullet and you look and say, “$hit, I’ve only got 1200 more to do” It was absolutely crazy.

So, you’re loaded your rounds, you stick them in the comparator, measure them, wiggle it a slight bit, measurement changes a few thousandths. You shake your head, only 1200 more to go.

I decided that it was nuts to try and get them absolutely perfect. That being said, I shot one of my best 1K prone matches with 107 SMK’s that I measured ad nauseam. I since switched over to Berger 108’s for the Dasher and found very good consistency, measuring, if I‘m within a couple of thousandths, I call it good. The results on the target haven’t suffered because of it.

According to the Precision Rifle Blog article on throat erosion, a Dasher barrel‘s throat lengthens .004 for every 100 rounds fired. If so, having ammo that only shoot’s accurately at a very specific measurement is going to be out of spec after a relatively low number of rounds fired. In a two day match, up to 200 rounds are fired, if you’re that OCD about the measurement of your bullets, it’s amazing they make it to the target. (They‘ll probably shoot just fine and you didn’t realize the change in the length of the throat)

As been tested and said, there’s a window of round length that will shoot just fine, you do need to work and figure out what the average is, and go from there. Your throat will lengthen with use and chasing the lands is a futile effort IMO. I had a Dasher barrel that I setup for a specific round length, I didn’t measure it through the season, as it kept shooting great. At the end of the year, I measured the throat and found that my .010 jump had increased to about .040, I got scared, how could this be? The rifle hammers and wins. I did adjust the jump back to .010 and confirmed all was good, on from there...

 

[dgeesaman]

I think Dusty is right, getting the seating stem to engage well with the bullet is most important. While an arbor press is mechanically cleaner and theoretically better for seating, the forces involved IMHO are always small enough that the difference is irrelevant, provided the press and die are good quality.

One advantage to the arbor is arbor die stems change easily and are already available in VLD styles. But they do the same thing so I’d call my seating die supplier to see if they have a VLD stem option.

The other thing to explore with the stem is fit to the bullet surface. First confirm the stem is contacting the ogive and not the tip. Then you can lap or bed the stem to the bullet to further improve that contact.

Neck tension (seating force) is critical too. Brass is springy including the lengthwise direction. So if it takes more force to seat a particular bullet, the case will flex downward more than the other cases, and the final length out of the press will be longer.

I personally have dealt with inconsistent friction inside the neck. This causes wildly inconsistent seating forces and CBTO also. At the time I was relying on residual carbon from previous firings. That has improved greatly since I started using expanders and dry case neck lube.
One bonus feature of arbor seaters: you can easily get one reamed using you reamer for outstanding fit over the cartridge. Whether or not that matters is like everything else: arguable.

 

[foxguy]

Along with the brass's neck tension and dry Lube, I believe the consistency of speed ( ie slow and steady verses fast) with which you pull the seating presses handle can cause a variance in the seating depth of the bullet .002-.005 .

 

[Liven The Dream]

I was having this issue with my .284 and Burger 180 HB.
I have Whidden Bushing Dies and Necked up 6.5-284 Laupa.
The lot of 1000 Bullets is a Train Wreck. BTO .001 to .008 variable.
I am getting a .0015 to .002 neck Tension , with sorted Bullet and slow Press operation my
rounds are with in .0005 to .001 with a odd ball once in a while ?

With New Brass Necked up this can be a different story.
Will be ordering a Mandrel !

Good Post

 

[TonyC]

I've looked at some of the previous "Inconsistent Seating Depth" threads and they're not providing a clear picture as to what I should do.

I'm shooting straight .284, Berger 180gr Hybrids; seating with a Redding Competition (Micrometer) die and RCBS Rockchuker press. Extreme spread of CBTO is .003"-.004". I'm finding it very frustrating. I've loaded batches with bullets sorted by BTO - and also with bullets sorted by OAL. Those different bullet sorting methods don't seem to have much impact on seating consistency.

I'm getting the sense the Wilson Micrometer Arbor Press die (with the VLD stem) seats based on bullet profile close to (or at) the ogive. Is that the case? Does the Redding (with VLD stem) seat more based on bullet tip?

Will that ES of .003"-.004" that I'm seeing likely be reduced if I go the Arbor/Wilson route? (If I go this route I'd also get the force pack - and so it appears an incremental benefit of taking the Arbor plunge is having seating force data.)

Input / Experiences?

Thanks!

CG

CG, I was wondering how many times have you fired this brass? What type of brass are you using? What chamber reamer are you using? It is possible you’re seating on a doughnut.

 

[CarlGeorge]

Wow - gotten way more input than I anticipated. Thanks!

Some additional context/facts:
* Necked up 6.5x284
* Annealed
* Necks not turned
* Not sure of chamber reamer used
* Shouldn't be any donut issues. Gun was built by Emil Kovan - and we discussed donuts when deciding on freebore (ended up being about .040" or so.....and I've gotten .008" of erosion since I took delivery.)

While I understand and accept neck tension is important to results on target.....and that case prep impacts neck tension.....I'm struggling to see how differing amounts of neck tension impacts resulting seating depth UNLESS there is play in the (non-Arbor) press and the differing neck tension brings out / highlights / moves the linkages that make that play a factor. For example, a case with neck tension A might cause the press to deflect X but a case with neck tension B might cause the press to deflect Y. With a conventional press there are a whole bunch of pins/linkages between the shellholder and press's die threads. It strikes me as a vulnerable part of doing things consistently.

If this is true, then I can see how an Arbor might help the situation. Essentially, it seems to me, the consistency between shellholder and seating stem is within the die itself. It's a much more constrained/restrained system.

Richard in post #10 makes a comment about consistency of press handle manipulation. I can definitely cause differences based on how hard I press on the handle at the bottom of the stroke. I pay a lot of attention to (trying) to finish the stroke the same way every time. I've had sessions where I've seated 20 or so rounds and every single one was dead-nuts on. And others where every round coming out of the seater was different.

But the above statements assume consistency in where the stem hits the bullet and where the comparator does. Before now I hadn't checked specifically where each of those touch the bullet. See photo. In the middle is the Redding VLD stem, and on the right is my comparator. If bullet manufacturing can be (is?) inconsistent from ogive to tip, then this pic alone helps me better understand the issue. I'm seating off of one datum point and expecting consistent measurement using a different datum point. Sounds like a making for an exercise in futility. And if Wilson's stem doesn't go farther down the bullet, I can see how I might have similar frustrations with an Arbor setup.

 

[urbanrifleman]

With a tiny arbor press and a Wilson die you can FEEL all the seating tension flaws. A standard press is a barbell by comparison. Being able to feel the problems is the first step to solving them.

 

[Richard Coody]

Sounds like you are getting the picture. If you sort a group of those perfect rounds and some of your worst and shoot them the target will let you know if it Is it really worth the trouble.

I find berger bullets have the most consistent ogive of mass produced bullets

I know with careful brass prep using a 21st century arbor press I can get neck tension consistent and my seating depth doesn't vary .001. Concentricity is negligible too! Is it worth it. For my bench gun maybe a tenth in group size with really good consistency. Of course there are a lot of other things that went into that

 

[acloco]

What are the size of the groups at 300/600/1000 yards now?

 

[Tod Hendricks]

With a tiny arbor press and a Wilson die you can FEEL all the seating tension flaws. A standard press is a barbell by comparison. Being able to feel the problems is the first step to solving them.

Do this, purchase a separate seating system, the results will immediately tell you if the problem is your Redding die and press. Use both systems to test against the other for fine tuning of your procedures.

More than likely it’s a combination of factors that you will need to diagnose, all mentioned above.

You can ignore it and probably be ok most of the time, that goes against a precision minded reloaders nature.