To Arbor Press or not?

One thing I've noticed with an arbor press is when you adjust the seating die for a certain CBTO length, you get that length each time. There is no flexing of the press between the shell holder and the die. The runout is probably more consistantly low too, although I've never done a study to prove it.

I've had good results using an old RCBS Rockchucker when I use a chamber type bullet seating die from Redding or Forster.

I use one simply because I think it's more fun to seat that way.

@Cold_Bore_88 I will never use a conventional press for seating ever again and will not shoot a new caliber for which I can't reasonably get an arbor seater die.

Think about what is happening when you seat using a conventional die:

1) You place the case/bullet into the shell holder on your press. It may or may not be perfectly aligned. This is opportunity for error #1.

2) You then pull down on your press handle and move the case/bullet about 6 inches up and into the die situated above it. As @ShtrRdy says, there is a certain amount of play involved with all that movement. Opportunity for error #2.

3) You then reverse the whole thing and move the case back down about 6 inches.

No real opportunity for error in this last step, but that's a whole lot of movement, mechanical linkages, and overall opportunity for error to do what? Move a bullet less than half an inch. It's a horribly inefficient process designed around using the same tool (the press) that was really designed around the sizing step. In short, the standard reloading press is not optimally designed for seating - it's the wrong tool for the job.

With an arbor press, you get perfect alignment every time, the case doesn't move, and the only engagement with the case/bullet is specifically the less-than-half inch movement of the seating stem pushing the bullet down.

Other significant advantages of an arbor press and associated seaters:

- You can take the thing to the range for seating depth testing and adjust while you're there. At a minimum it saves you a trip to the range to validate a good looking depth.

- You can measure seating forces and hone your process to optimize for seating force consistency, as well as cull out "fliers" as needed.

I count getting my first arbor press as one of the most important equipment additions I've done to my reloading process. This was the K&M with the standard force pack. I still have it and use it for the aforementioned range trips. I use the AMP Press for all my in-home seating needs and record every batch of ammo.

Entropicitis said:

I use one simply because I think it's more fun to seat that way.

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It's way more zen to use the arbor press.

An arbor press with a Wilson type seating die is as old as the hills.....

If you can't get to a club level BR match to see one in action, then you will just have to decide if you will buy that type of stuff or not.
In my opinion, you owe it to yourself to get to a well attended match and watch those guys and what they do.

When you care about seating force, or when you do load development that is sensitive to neck tension or seating, you will run an arbor style die and press at the range.

If you do this and find it isn't for you, I doubt you will loose very much value when you sell it. YMMV

Cold_Bore_88 said:

Looking for anyone with experience running an arbor press and how it compares to a conventional press. Did you see obvious results in down range performance?

I am also interested in an arbor press because it is more portable and less “work” in turn of cam over and effort.

As a follow up, has anyone seen a digital force gauge that could be used with an arbor press? I see the AMP option but I don’t want to spend 1500 on another press. It would be cool if you could retro fit a simple digital force pac to the lower priced options like K&M or 21st Cnetury.

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I've been running Wilson dies, my own handmade dies and an old Sinclair Arbor pres for more years than I care to admit. I do that for my "Bench" guns, but I wouldn't even consider it for anything else. Just not worth the effort.

Others may feel differently, but I've never been attracted to any kind of force gauge set up. I've always done my hand die/arbor press loading by feel. Would a force gauge be more "accurate" ? Yep, probably. But, I don't think that's the proper way to look at it. You still have to load all your rounds to the same Jump, and the force gauge does not directly affect OAL or CBTO. If you adjust based on "consistent" force, you'll end up with loaded rounds of different (OAL or CBTO) lengths.

If you find one (or more) round(s) that is out of whack (by using a force gauge), relative to the rest, realistically, what are you going to do about it ? Tear it down, turn the neck (assuming too high of neck tension because of "excessive" neck thickness ? Not a very attractive option.

Or even worse, what if one round has (way) too little neck tension ? Are you going to tear down all your loaded rounds, turn the other thicker necks to match the one piece of brass and go to a smaller button on your neck resizing die ? Just a lot of work and a high probability of becoming a monkey chasing it's tail.

When I prep brand new (Lapua) brass, I neck turn with a K&M turning tool and arbor/mandrel. I go at a relatively slow pace because I have noticed that if I go too fast, I will get brass that has had too much material removed from the neck area. I assume this is because the mandrel is swelling due to getting warm/hot. Not sure if I'm right, but it makes sense that that could be what is happening. And yes, I use Imperial sizing die wax liberally.

Finally, yes, I have a relatively small Flambeau fishing tackle box that has all my (hand) reloading gear in it so that I can reload at the range, should I choose to.

Cold_Bore_88 said:

Which arbor press are you using?

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I have a K&M. I use it for smaller cartridges. I tried it once for seating bullets in a 308 Win case and it was difficult. I attributed the difficulty due to the short handle on that press.

Is there an aspect of your loaded cartridge you would like to improve? You mentioned monitoring seating force.

Cold_Bore_88 said:

It would be “nice to have” the ability to set rounds with excessive force to the side for shorter range PRS stages (200-500). The consistent rounds would be used for smaller 1 MOA targets beyond 500. I would also like more consistent seating depth from round to round. I am seeing .002+/- with my CO-AX press and Forster seating dies.

The ability to seat bullets with less work would be nice too.

I heard the 21st century arbors are great too but bigger.

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The 21st Century might be a good choice then.
For piece of mind it would be good to cull out any cartridge that requires significantly different force to seat the bullet for competition use.

Cold_Bore_88 said:

I wish the indicators held at peace force and then could be manually reset to zero. Having to watch where peak force occurs is kinda annoying.

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It's actually not so bad. What else are you going to be watching when you're seating?

Cold_Bore_88 said:

I guess that’s why people get the AMP.

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I gotta say... it's nice. Actually, the plotting of the curve is really good. Helps identify donuts and other potential inconsistencies and is a lot more accurate. The ability to save them and go back to review later is great as well. It's a tad bit slower than a hand press, but then I can also sit at my computer while reloading, which is a bonus sometimes.

Threadcutter308 said:

If you find one (or more) round(s) that is out of whack (by using a force gauge), relative to the rest, realistically, what are you going to do about it ? Tear it down, turn the neck (assuming too high of neck tension because of "excessive" neck thickness ? Not a very attractive option.

Or even worse, what if one round has (way) too little neck tension ? Are you going to tear down all your loaded rounds, turn the other thicker necks to match the one piece of brass and go to a smaller button on your neck resizing die ? Just a lot of work and a high probability of becoming a monkey chasing it's tail.

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When a round falls outside of my desired tolerance, I don't break it down, I just mark it with a Sharpy and use it for less critical shots (fouling/warming, shorter range, sighting in, etc.).

Also, there are reasons other than neck tension that can cause differences in seating forces. It doesn't necessarily mean the case is bad - it could have been something during case prep. I'll look at the higher force cases after they're fired to see if there is any difference in neck thickness, donut forming, etc.

Usually there is nothing. Of note is that my tolerances are very tight and only have about 2-3 rounds per 50 that I mark.

If you’re using say Lapua brass from the same lot you’re not going to have enough seating pressure variance to warrant culling unless your case prep is shit.

Rocketmandb said:

When a round falls outside of my desired tolerance, I don't break it down, I just mark it with a Sharpy and use it for less critical shots (fouling/warming, shorter range, sighting in, etc.).

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I have been doing this for a while during every seating session, usually only 10-20 rounds at a time - just what I plan to shoot the next day (I have my own range, and shoot about 3x/wk, so I feel I learn more from multiple short sessions in many different conditions than one long session in only one condition). When the seating session is over, I look at the traces on the AMP graph, and mark the round with the highest seating force by using a red Sharpie on the primer. Then I mark the primer on the round with the lowest seating force in black. I have been looking for trends to see if the red or black-colored rounds consistently fall in either the lower or upper end of my ES for that session. To date, over many sessions, I have not been able to establish a trend. They seem to fall randomly within the ES for the session. BUT, because of the advantage of the AMP (being able to identify and fix problems in brass prep and see the results), I don't have a wild variance in seating force - usually 20-25 lbs difference between lowest and highest, with most falling in the middle with a range of about a 10 lb dlfference.

Cold_Bore_88 said:

I am a buy once cry once guy so I am slowly moving towards the AMP. It would be nice to just sit there and let it do the work.

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...while you are throwing the powder for the next round. My IP trickler is done with the next charge at about the same time the AMP is finishing the seating on the previous round, so my hands are in constant motion, never really waiting on anything: Pour a finished charge into a case, set a bullet on it and into the seating die, place it on the AMP (set to Autorun), start the next charge to be thrown/trickled, go back and remove the now-finished previous round from the AMP, and the next charge is now finished and ready to be poured into the next case, etc, etc.

Cold_Bore_88 said:

I am a buy once cry once guy so I am slowly moving towards the AMP. It would be nice to just sit there and let it do the work.

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I wouldn't exactly say it's that easy...

However, using it to hone your process to get plots like this are very satisfying. And this is a little higher spread than normal for this caliber (6 BRA).

Cold_Bore_88 said:

Without jumping straight into an AMP, would you recommend the K&M or 21st century hydro arbor press?

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I have not used the 21st Century products, but will give some insights regardless:

- 21st Century now has a press very similar to the K&M. It looks more substantial, but doesn't appear to be able to take a force pack/gauge. It has the same large wheel that tightens against the vertical post for doing adjustments that the other presses have. The K&M has two allen head screws that need to be loosened/tightened for adjustments.
- 21st Century also has their "New Generation Arbor Press" which has a much more substantial handle (similar to the Hydro Press)
- The go-to with 21st Century for a long time has been their hydro press, which is really freaking nice and has a force gauge built in.
- The cantilevered handle on the Hydro allows for finer and slower operation of the press, which allow for easier reading of the force gauge
- Except for the new Arbor Press, the 21st Century units have a bigger footprint. This carries positives and negatives.
- One of the positives is that it will be more stable than the K&M. With longer cases on the K&M it can get a little tippy as you apply force to the handle.
- In the plus column related to this for the K&M is that it is very portable so is more range appropriate.
- My only real complaint with the K&M is that the thumb screw that secures the handle is tough to keep tightened down so occasionally has to be reset.
- Some people don't like the short handle on the K&M. You can always get a longer handle made, it's just a rod with a knob on the end that is secured with the aforementioned thumb screw, but it's also an extra thing.
- Both companies make high-quality equipment, but I'd put 21st Century higher in this regard. I really like their stuff.
- The K&M is less expensive, if cost is a factor.

As it stands, I'm happier that I initially went with the K&M because as it's now my backup press I can easily take it to the range and I use the AMP as my primary. However, if I was only going to buy one press, and taking it to the range was not as important, between the K&M and 21st Century products it would be the 21st Century Hydro.

Iv got a k&m without the force gauge.

With that short handle it’s not hard to feel if something is different or off.

I will set different feeling rounds on the side for practice.

The arbor press has also really taught me a lot about what processes aid in making more consistent neck tension and what didn’t.

Plus they are cheap and easier to use than the big press imo