JamesnTN said:I can see a difference on paper with only .0005 difference in neck tension
Steve Wilson said:Ben, you mentioned a light lube between your fingers; what kind of lube?
Here is how I use my Hydro Press. Brass annealed after every firing. One stroke with a blue Iosso brush inside the dirty neck, followed by Redding powdered graphite on a Q Tip for lube. My necks are no turn and seating pressure runs right at 20 PSI on both my 6BR and 6 Dasher. When I load 100 rounds for a match, the range of pressure will 19 to 21 for the majority. There always seem to be a couple of oddballs that come in at 18 or 22, those go in the fouler row. All 40 rounds shot for record will be the exact same reading, usually 20 PSI. The rest will be organized to 1 PSI readings. You WILL see elevation changes at 600 yards between say 20 and 40 PSI.
Hope this provides some usefull information.
Before the 21 Century seating tool a reloader could determine the effort required to seat a bullet.
Not true,
Currently there is no tool available to measure neck tension.
I understand interference fit, I understand crush fit. There are not many tools I do not have. The one thing I do not have and can not find is a conversion for tensions to pounds.
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21st Century Bullet seater press
« Reply #19 on: 09:39 PM, 02/12/15 »
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A question for those that use this press...
If you size a case .002 down from loaded dimension it's relatively safe to say you have .002" "Neck tension" .
Steve Wilson said:Ben,
I use slow and steady pressure on the handle through the entire seating process. You can feel the boattail slip into the neck at around 10 PSI, in my case. Then it requires more force on the handle to seat it. Keep increasing pressure gradually and watch the needle climb. It reaches a certain point and then you can see the seater die start moving down again. With your eyes shifting between the seater die and the needle, you will notice that the PSI will remain steady once the actual seating process begins. I go slow.
It's sort of a co-ordination thing to dance your eyes between the die and the needle as you apply pressure to the handle. After awhile you get a feel for the whole thing and don't pay much attention to the gap in the die. Instead, you develop a sense in your hand as you are pushing down on the handle and watching the needle. Gauge comes up to 10 PSI (or whatever number you get), handle drops down a bit...there, the boattail just went in. Pressure steadily rises on the needle, then at some point on the gauge you feel the bullet smoothly seat as you keep lowering the handle. Like I said, it's a sort of co-ordinated thing. Try going slower, I think you will see what I'm talking about.
Also, round up some fatter Q Tips from Sinclair. The Wallgreen's ones work too but fit looser in a 6 BR neck. Dip the Q Tip in the graphite powder, tap it on the jar to knock off the excess and then lube 3 to 5 necks. Dip again and repeat. A used Q Tip fuzzes up some and works better than a brand new one. You will get a few crumbs on your fingers, the shoulders and the loading block. Can't avoid making some little bit of a mess, but the graphite works wonders in uniforming the required seating force. I graphite all of the necks before I put the powder in.
Go slower, try the graphite again and let me know if you see improvement. Those Hydro Presses are the slickest things going but it takes a little time to develop a sense for the process.
NO..Patch700 said:if you were to take a case that had an ID of .243" and ran it up onto a .264" mandrel that there would be .021" of tension gripping that mandrel?
mikecr said:NO..Patch700 said:if you were to take a case that had an ID of .243" and ran it up onto a .264" mandrel that there would be .021" of tension gripping that mandrel?
All you had was 21thou interference.
Your tension is no more than provided by spring back of your now sized brass against the 264 mandrel,, which is ~.5-2thou.
This isn't complicated folks.
Where you increase seating friction, including sizing necks with bullets, you increase seating forces only -nothing to do with tension.
Tension is thickness of brass hardness springing back to grip bullets.
So variance in tension is variance in hardness and/or thickness of it.
You cannot even pretend tension correlates with seating forces without very carefully controlling thickness and seating friction, and you won't get there without at least understanding these terms.
No wonder we can't communicate our ideas and efforts.
Tension is one of them, you cannot have 2 thou of "tension"... one is a liner measurement, and the other is force, and they do not relate or convert.