Is the K&M Arbor Press w/ LE Wilson Seater Dies - Neck dies worth it, consistency, accurate..

Been contemplating an arbor press with force gauge for my ELR stuff
Finishing sizing with an expander certainly helped with vertical.
Press cost with inline seater is reasonable.

I’m actually faster with my hydro press.

It’s also useful for being able to either work with a single case a couple times or marking it and looking at it over a firing or three. If it’s repeatedly showing inconsistencies, I just toss it. It’s not worth the $1 case to try to figure out why one won’t act the same as the rest.

And in the event you’re getting really random numbers, you know you need to assess your process.
 
I found the concentricity to be superior with the dies used with an arbor press, but the main gainer is knowing what your seating force is. Being able to put aside (as foulers, or whatever) rounds that fall outside whatever seating force range you're okay with makes a fair amount of difference in consistency of the rest. With my current process, I put aside about 1 out of 10.

The last time I measured all the rounds I loaded for a trip to BLM land (a couple months ago), I got an SD of right at 6 with my 300 PRC. That was, if memory serves, 44 rounds. I used a couple of the foulers to warm the barrel up, then shot the good rounds. That SD is pretty consistent with other trips with my 300. With my 6 BRA, I'll get mid-4s across a similar number of rounds.

I had good SDs before I got the arbor press and associated dies, but not quite this good. The dies play a role, but it's more the additional steps I put in place once I realized how much variation I had in seating force because of the force gauge on the press.

1 out of 10 is a really high number. You are stating that 10% of your reloads are unacceptable? I think that has to be more process related then equipment related.

I reload on a Forster Co-Ax, using Whidden FL dies, powder being thrown with an Autotrickler & FX-120i. I rarely throw out any reloads, not unless something is obviously wrong. I don't measure seating force. Across all the cartridges I reload for (6BRA, 6.5 Creedmoor, .300NM), I get SD's between ~4-5.

I'm not sure if I buy the concept that an Arbor press provides performance gain beyond any marginal manner. You bring up concentricity, but have you isolated all other variables, while varying concentricity, and determined that there is a consistently measurable precision gain with concentricity? I don't measure concentricity, so I have no clue how concentric my rounds are or not, but my targets show no need to place a focus on it.

What about seating force? What factors go into seating force? What is considered "acceptable" seating force, and what determines that? Have you isolated all variables while varying seating force and determined any consistently measurable performance gain attributable to that variable?

Now, I'm not saying what I do is the be all end all, or that there is no room left for performance improvements from my own reloads. But I'm a bit skeptical of some of these claims. But hey, if they work for you, then I guess that's all that matters.
 
1 out of 10 is a really high number. You are stating that 10% of your reloads are unacceptable? I think that has to be more process related then equipment related.

I reload on a Forster Co-Ax, using Whidden FL dies, powder being thrown with an Autotrickler & FX-120i. I rarely throw out any reloads, not unless something is obviously wrong. I don't measure seating force. Across all the cartridges I reload for (6BRA, 6.5 Creedmoor, .300NM), I get SD's between ~4-5.

I'm not sure if I buy the concept that an Arbor press provides performance gain beyond any marginal manner. You bring up concentricity, but have you isolated all other variables, while varying concentricity, and determined that there is a consistently measurable precision gain with concentricity? I don't measure concentricity, so I have no clue how concentric my rounds are or not, but my targets show no need to place a focus on it.

What about seating force? What factors go into seating force? What is considered "acceptable" seating force, and what determines that? Have you isolated all variables while varying seating force and determined any consistently measurable performance gain attributable to that variable?

Now, I'm not saying what I do is the be all end all, or that there is no room left for performance improvements from my own reloads. But I'm a bit skeptical of some of these claims. But hey, if they work for you, then I guess that's all that matters.

You’ll see “small” gains culling things outside of consistent seating force.

By small, I’m talking decreasing a 25es to 20. But that’s a big deal when shooting as small as possible at distance is your goal.

Is every round that you cull via seating pressure be a dud or throw your ES off? Nope. But if you’re attempting to shoot small, even if 1/10 that guy culled (1/100 in a 100 count where you culled 1/10), thats the difference in sending a shit significantly low or high compared to the size you intend to shoot.
 
I was able to locate items in stock, Arbor press, dies and other items needed to have a complete setup for 223 Rem, 6 Dasher and 6.5 CM. Will have by end of next week if all goes well and UPS does their part. The 4 to 6 week wait from Wilson didn't work for me.
I guess the journey begins, will update my results after getting my barrels settled in. Plans are to chrono every round fired and capture SD - ES data with some grouping.
Thanks to all that contributed, well most, really looking forward to seeing the results.
 
By small, I’m talking decreasing a 25es to 20. But that’s a big deal when shooting as small as possible at distance is your goal.

On my 300 at 2000 yards, 25 to 20 is between 1/4 and 1/3 of my target width, so I try to get as low as possible.

As an aside, I know you neck turn - did you see much improvement vs. just using a mandrel? Since trying neck turning (unsuccessfully) a couple years ago, I haven't tried again.
 
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On my 300 at 2000 yards, 25 to 20 is between 1/4 and 1/3 of my target width, so I try to get as low as possible.

As an aside, I know you neck turn - did you see much improvement vs. just using a mandrel? Since trying neck turning (unsuccessfully) a couple years ago, I haven't tried again.

Ya, it definitely matters. “Small” is actually a pretty big deal at distance.

I haven’t neck turned a lot lately just cause lazy.

But in my experience, it knocks ES down another few fps. I get my absolute best results when I neck turn (inside and out), mandrel, check with pin gauge, and cull via hydro press.

But, we are now getting into numbers that’s almost impossible to exploit without a $900+ front rest and 20lb+ rear bag.
 
1 out of 10 is a really high number. You are stating that 10% of your reloads are unacceptable? I think that has to be more process related then equipment related.

I've got a fairly tight tolerance on my seating force (~10 - 15 lb spread). As @Dthomas3523 mentions, it doesn't mean they won't shoot, just that they are out of what I've set as acceptable.

I reload on a Forster Co-Ax, using Whidden FL dies, powder being thrown with an Autotrickler & FX-120i. I rarely throw out any reloads, not unless something is obviously wrong. I don't measure seating force. Across all the cartridges I reload for (6BRA, 6.5 Creedmoor, .300NM), I get SD's between ~4-5.

With that setup, what reason would you possibly have to throw out a reload? The force gauge is what tells you a round has higher or lower "neck tension", which is in itself a misnomer.

I'm not sure if I buy the concept that an Arbor press provides performance gain beyond any marginal manner. You bring up concentricity, but have you isolated all other variables, while varying concentricity, and determined that there is a consistently measurable precision gain with concentricity? I don't measure concentricity, so I have no clue how concentric my rounds are or not, but my targets show no need to place a focus on it.

Please go back and read my post again. I definitively did not say that the arbor press made my ES/SDs go down a dramatic amount. What I did say is, "the dies play a role, but it's more the additional steps I put in place once I realized how much variation I had in seating force because of the force gauge on the press."

What about seating force? What factors go into seating force?

Very simple: coefficient of friction between the bullet and inside of the neck, area of the bearing surface, and force imparted by the neck caused by the difference in size of the bullet being inserted vs. the internal diameter of the neck. This is influenced by the properties of the brass in the neck itself.

What is considered "acceptable" seating force, and what determines that?

I set what is acceptable based on my goals. Right now, it's ~10-15 pounds of variation.

Have you isolated all variables while varying seating force and determined any consistently measurable performance gain attributable to that variable?

I've landed on two things providing a discernable difference: uniforming the inside neck diameter using a mandrel and using graphite neck lube.
 
I haven’t neck turned a lot lately just cause lazy.

But in my experience, it knocks ES down another few fps. I get my absolute best results when I neck turn (inside and out), mandrel, check with pin gauge, and cull via hydro press.

What tool are you using? If I'm going to try it again, I don't want the equipment to be the reason I fail at it a second time.
 
Appreciate the conversation, I'm genuinely curious. I don't like adding steps to my reloading process if I don't have to, and with my current process I see and ES of ~15-20 fps throughout the cartridges I reload for.

For me that's acceptable.
 
What tool are you using? If I'm going to try it again, I don't want the equipment to be the reason I fail at it a second time.

I have a 21st century lathe for taking small cuts like .0005-.001. It only turns the outside.

And I have an IDOD that does inside and out. But since it doesn’t run on a mandrel, it’s bound by the Concentricity of the case. So .001-.002 is the minimum you’ll be taking off the neck.

Not that “excessive” neck clearance does anything except *possibly* having split necks sooner. But some people don’t like cutting down and having .008 or so clearance around necks.