School me on Bullet seating force tools

[Hengehold]

I have read some posts on this site and the K&M press with force gauge seems to have favorable reviews. Are there any other seating force measurement tools or models that are better than the K&M?


I read of a press that used a hydraulic gauge rather than the standard force gauge. Would a hydraulic system be better or just a different way to get the same results?

Thanks,
Trevor

 

[jlow]

No one has ever come up with a reason one is better than the other. BUT you do get the honor of paying more if that is important to you, so I guess bragging rights if that is important.

 

[MagnumManiac]

Seating force has little to do with accuracy.
Bullets and brass give different force ratings as they are seated depending on hardness.
Bullets are released by neck expansion, not interference force/neck tension, as most believe. As soon as the primer ignites, the neck tension is lost, just as it is if you re-seat a bullet or pull it.

I don't see any advantage knowing how much force is needed to seat a bullet if for only deducing whether the brass hardness is uniform. A commercial hardness tester could tell you that, if you wish.

Cheers.

 

[jlow]

Seating force has little to do with accuracy.
Bullets and brass give different force ratings as they are seated depending on hardness.
Bullets are released by neck expansion, not interference force/neck tension, as most believe. As soon as the primer ignites, the neck tension is lost, just as it is if you re-seat a bullet or pull it.

I don't see any advantage knowing how much force is needed to seat a bullet if for only deducing whether the brass hardness is uniform. A commercial hardness tester could tell you that, if you wish.

Cheers.

Sorry but totally wrong. You are only right if the bullet release is an all or none phenomena which it is not.

Just because the release happens in millisecond time frame too fast to see does not make it an all or none phenomena, it still takes time.

The time difference between a consistent release time and a varied inconsistent release time is what affects the time it takes the bullet to reach the crown which means it affects barrel time, which in turn means it affects precision.

 

[JohnKielly]

.... but what evidence do we have that seating pressure is related to release pressure?

 

[tuttlefarm]

Seating force has little to do with accuracy.
Bullets and brass give different force ratings as they are seated depending on hardness.
Bullets are released by neck expansion, not interference force/neck tension, as most believe. As soon as the primer ignites, the neck tension is lost, just as it is if you re-seat a bullet or pull it.

I don't see any advantage knowing how much force is needed to seat a bullet if for only deducing whether the brass hardness is uniform. A commercial hardness tester could tell you that, if you wish.

Cheers.

You are really off base with your comments. Erratic seating force has everything to do with accuracy. Some rifles shoot very well with light seating force and others like the 300 wsm like alot of seating force.

 

[jlow]

.... but what evidence do we have that seating pressure is related to release pressure?

Think.....

 

[Erik Cortina]

I have both, the K&M and the 21st century. The 21st century is by far superior.

 

[jlow]

I have both, the K&M and the 21st century. The 21st century is by far superior.

Please tell us how?

 

[Hengehold]

I have both, the K&M and the 21st century. The 21st century is by far superior.

Excuse my ignorance but I have never used an arbor press or a seating force Gauge before. Please share your reasoning. I would like to hear what makes one better than another.
-Trevor

 

[JohnKielly]

Think.....

My thought when I wrote that was that there should be a direct relationship when the seating doesn't expand the neck beyond its elastic limit and the Lee company aver that might be no more than a few thousandths of diameter expansion, but if it goes beyond that....? I have a 458 Winchester given me by a safari guide I me once & you can see where the bullet ends in it by where the goiter stops on the case. Who knows what the relationship is there.

BTW, I surmised that somebody had loaded virgin brass without neck prep to get that result, but I've seen some factory loads exhibiting the same neck constriction below the bullet.

 

[Alex Wheeler]

Magnum is not off base on this. Bullets are released after the neck expands. If this was not the case the neck would not expand at all. Seating force is FAR more dependent of the friction between the case and the bullet than the actual grip the neck puts on the bullet. You can test this very simply. I have tested this as well as on target. However, this is all within reason. If you are seeing 50 lbs between cases thats something different. I was loading for a 1k yd match in a hotel room, I had forgotten my brass and was stuck reloading the stuff I had. Seating force was bad, 15-20 lb es. That 10 shot group measured 4.1"

 

[Keith Glasscock]

In the big scheme, it doesn't matter what the seating force gauge reads.

When we start looking for that last .01%, everything has an input into the results.

I like my hydro seating press. It has taught me a lot about my brass and brass prep. My average accuracy is the same, but I spend less time fooling around trying to batch ammo.

 

[zx10mike]

i have been batching by seat force.i have been annealing by hand to date but i'm now using a machine .in the next week or so i'll be loading some up and hope that i see a big improvement in consistency .in my opinion if a bullet takes more force to go in it will take more force to go out.right or wrong it helps me have faith in my ammo.

 

[DOGCAPPER]

zxmike is correct in batching bullets by force. Until you acquire a force guage from Sinclaire note handle pressure when seating, Put heavy in one row not so heavy in another and so on. Really light and really heavy in the warmup row. Watch what happens and make up your mind what is needed.

 

[memilanuk]

So... question for you guys that use these things more. When I use a regular press with threaded dies, its set up to run to a stop. When it stops, the seating depth is what it is... consistently, pretty much every time, +/- 0.001". Yeah, if I lean on the handle I can fudge that either way a bit, but with normal sane operation, its remarkably consistent.

When I use a hand die in an arbor press... it suddenly becomes *very* dependent on the seating force. If the die is set for seating depth with cases that have relatively light neck tension, and I have one case that has heavier neck tension... that one is going to be longer. Pretty much every time. And vice versa... if I have it set at a heavier neck tension and come across a case with lighter neck tension, that bullet is going to be seated a couple thou deeper - every time. The die is going to full 'stop', just like on the threaded press - or at least it feels like it - but the result is very different.

It's very frustrating... in theory the arbor press and hand dies should be giving more consistent seating, but in actual practice I end up chasing the seating depth all over and getting generally irritated with it. I find myself using the seating force tool more as an indicator of whether or not the seating depth is consistent, than any special neck-tension magic. Or I can load the same rounds on my Co-Ax or 550 and have more consistent seating depth, with less headaches.

What's going on here?

 

[Hengehold]

So... question for you guys that use these things more. When I use a regular press with threaded dies, its set up to run to a stop. When it stops, the seating depth is what it is... consistently, pretty much every time, +/- 0.001". Yeah, if I lean on the handle I can fudge that either way a bit, but with normal sane operation, its remarkably consistent.

When I use a hand die in an arbor press... it suddenly becomes *very* dependent on the seating force. If the die is set for seating depth with cases that have relatively light neck tension, and I have one case that has heavier neck tension... that one is going to be longer. Pretty much every time. And vice versa... if I have it set at a heavier neck tension and come across a case with lighter neck tension, that bullet is going to be seated a couple thou deeper - every time. The die is going to full 'stop', just like on the threaded press - or at least it feels like it - but the result is very different.

It's very frustrating... in theory the arbor press and hand dies should be giving more consistent seating, but in actual practice I end up chasing the seating depth all over and getting generally irritated with it. I find myself using the seating force tool more as an indicator of whether or not the seating depth is consistent, than any special neck-tension magic. Or I can load the same rounds on my Co-Ax or 550 and have more consistent seating depth, with less headaches.

What's going on here?

Interesting, Is inconsistent seating depth with an arbor press something that everyone else experiences also?

If so, what would be the point of using an arbor press rather than a press like the RCBS Rockchucker? Seems like the arbor press would be a poor choice if that were the case.

-T

 

[500Stroker]

QUOTE="zx10mike, post: 36911726, member: 1285956"]i have been batching by seat force.i have been annealing by hand to date but i'm now using a machine .in the next week or so i'll be loading some up and hope that i see a big improvement in consistency .in my opinion if a bullet takes more force to go in it will take more force to go out.right or wrong it helps me have faith in my ammo.[/QUOTE]
You hit the nail on the head.
I have been sorting by seating force and I have seen a measurable reduction in group size.

 

[mikecr]

You can't begin to compare tension(bullet grip), as correlating with seating force, until friction is first removed as a variable.
But this far into discussion, at least we've dismissed interference fit, and friction, from actual tension.
That's a pretty big evolution right there.

One seating force tool -vs- another, hydraulic gauge, mechanical force?
I use a Sinclair expander mandrel die setup with electronic load cell for seating force comparison.
And there are other ways to achieve the same. It's just for comparison, not actual tension, so pick any.

 

[jlow]

First seating force measurements is measuring a lot of different things. Things that can affect seating force includes:

1. ID of the case neck (what some call neck tension).
   
   
2. OD of the bullet (trust me not all bullets of the same caliber is the same diameter).
   
   
3. Thickness of the case neck.
   
   
4. Consistency of the case neck thickness i.e. whether you neck turn or not.
   
   
5. Degree of work hardening of the case neck brass.
   
   
6. Consistency of the neck’s spring back i.e. how consistent you anneal it.
   
   
7. Friction between bullet and case neck.
   
   
8. Whether you chamfer the case neck and how smooth that chamfer is.
   

You are right that a linear increase in “neck tension” (i.e. ID) does not equate to a linear increase in tension on the bullet by the neck, but that is not important.

Obviously what you encounter in terms of resistance when you seat a bullet is NOT the same as what the bullet encounters when it exits the case neck. For one thing in the first instance, you have to expand the neck before you can enter, but in the second instance, the case neck is already holding the bullet. But as you imagine all of the above affects the seating characteristics of the bullet AND the release characteristic when the round is fired. So even though the absolute number you get when you seat the bullet is not a number that relates directly to the force encountered when the bullet exits the neck, they are related in a proportional manner.

This idea that bullets are only released after the neck is fully expands is pure fantasy….

The only way that the above neck characteristics would not affect the timing of the initial movement of the bullet out of the neck as I said before is if you can stop the bullet movement 100.00% while the neck expands and then let the bullet move forward. There is NO LOGIC that this can happen for obvious reasons. Logic would tell you that BOTH (i.e. bullet moves forward and the case neck expands) are happening at the same time. It is highly likely that as the bullet leaves the end of the neck, the case neck has expanded enough so that they do not interact – this is not a point of contention. The fact is though when the bullet first start moving, the case neck has not expanded enough to not interact with the bullet.

This is why differences in neck tension can affect the MV of a bullet and it’s precision.