That may tell you the force to seat the bullet but another test would be to seat them at different times and after sitting for a while, days, weeks, use a collet pullet and measure the force to remove the bullet. The ones that seated easier may be just as hard to pull, which may indicate the neck tension was similar with either method after time.
Time between sizing and seating; Does it have an effect?
- Thread starter Nodak7mm
- Start date
That may tell you the force to seat the bullet but another test would be to seat them at different times and after sitting for a while, days, weeks, use a collet pullet and measure the force to remove the bullet. The ones that seated easier may be just as hard to pull, which may indicate the neck tension was similar with either method after time.
Great comment
I anneal every time before sizing. Using one of those great Hydro seater arbor presses, this is how I adjust seating pressure to suit me:
15psi- 20 psi: anneal, rest the cases for 3 days, then size and seat.
20psi- 25 psi: anneal and size and seat on the same day.
25psi- 30 psi: anneal, size. Rest the cases for 3 days and then seat.
30psi- 40 psi: rest time a week or so.
40psi+: more than a week rest. The seating pressure spread and groups widen up.
This is just my experience.
15psi- 20 psi: anneal, rest the cases for 3 days, then size and seat.
20psi- 25 psi: anneal and size and seat on the same day.
25psi- 30 psi: anneal, size. Rest the cases for 3 days and then seat.
30psi- 40 psi: rest time a week or so.
40psi+: more than a week rest. The seating pressure spread and groups widen up.
This is just my experience.
BoydAllen
Gold $$ Contributor
The information that you have been so kind to share with us is pure gold, the like of which is seldom seen on forums. Thanks
BoydAllen
Gold $$ Contributor
Have you actually done a test? I have and the difference in force required to seat bullets is quite apparent. Anyone can feel it quite easily. The reason for test pilots is that engineered may not have visualized the problem correctly, so they have to do actual TESTS. This is not an alternative fact, it is actual experience that multiple reloaders have had. You know that thing you do with cases and dies and arbor presses...actually doing the thing.
No worries mate, all good 
Yes, more than a test, this is the experience of loading thousands of rounds using this system and these observations together with record keeping. I get a touch less runout and a touch more speed with 30 psi. Better grouping in my node with 20psi-25psi.
Until I stumbled upon a game changer as an add-on to this system:
Projectiles: Optimus 155.5 HBC (palma rifle) (HBN coated boat tails)
I tried sometime ago to use a Lee Universal Expanding Die, to flare the case mouths (instead of/ as well as chamfering).
My reasoning was (after trimming the cases and to make sure that they were square with the bottom of the case head- easy to do with your calipers, just run the case with your fingers on the jaws- if one side catches> not square) that:
If you flare the case mouths in diameter (at the rim only) by between 1 thou to 2 thou over your neck tension, you can have the smoothest seating in the history of mankind with the added bonus of not shaving bullet jackets and HBN coating in the process of seating.
My sweet spot is a quarter turn on the top of the die, after the expander makes contact with the case mouth.
Result: Seating pressure vs annealing+rest time stayed the exact same.
Extreme spread of seating pressure (high to low in same batch) came down from 11 psi to 2 psi per sample of 20 loaded rounds.
Average runout from 2.5 thou down to 0.8 thou.
In the real world there is a noticeable reduction in my group sizes.
I am more than happy to post as a reply to this post the procedure that I used to set up the die or to start a new thread, whatever you guys think is better. There is more info to it that I'm happy to share.
Very important when setting up the die, to make sure that the die base bottoms tight on the shell holder with a case in it before tightening the lock ring.
Yes, more than a test, this is the experience of loading thousands of rounds using this system and these observations together with record keeping. I get a touch less runout and a touch more speed with 30 psi. Better grouping in my node with 20psi-25psi.
Until I stumbled upon a game changer as an add-on to this system:
Projectiles: Optimus 155.5 HBC (palma rifle) (HBN coated boat tails)
I tried sometime ago to use a Lee Universal Expanding Die, to flare the case mouths (instead of/ as well as chamfering).
My reasoning was (after trimming the cases and to make sure that they were square with the bottom of the case head- easy to do with your calipers, just run the case with your fingers on the jaws- if one side catches> not square) that:
If you flare the case mouths in diameter (at the rim only) by between 1 thou to 2 thou over your neck tension, you can have the smoothest seating in the history of mankind with the added bonus of not shaving bullet jackets and HBN coating in the process of seating.
My sweet spot is a quarter turn on the top of the die, after the expander makes contact with the case mouth.
Result: Seating pressure vs annealing+rest time stayed the exact same.
Extreme spread of seating pressure (high to low in same batch) came down from 11 psi to 2 psi per sample of 20 loaded rounds.
Average runout from 2.5 thou down to 0.8 thou.
In the real world there is a noticeable reduction in my group sizes.
I am more than happy to post as a reply to this post the procedure that I used to set up the die or to start a new thread, whatever you guys think is better. There is more info to it that I'm happy to share.
Very important when setting up the die, to make sure that the die base bottoms tight on the shell holder with a case in it before tightening the lock ring.
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USMCDOC
Silver $$ Contributor
Ditto!
Because I do not have a tension gage I use bullet hold, again, I am the fan of all the bullet hold I can get; I would use tension if someone would sell me a tension gage. I have tension gages; none of my tensions gages are marked off in tensions, all of my tension gages are calibrated in pounds.
With bullets there is push and pull, I can not push in tensions, I can not pull in tensions but more times than not when I pull the trigger the neck expands before the bullet is released.
F. Guffey
With bullets there is push and pull, I can not push in tensions, I can not pull in tensions but more times than not when I pull the trigger the neck expands before the bullet is released.
F. Guffey
The properties of metal don't change with their application. I don't doubt that the seating force increases with time. It must be related to some other unknown factor. Someone earlier replied to this and said that if brass increased in tension with time, it would occur with or without a bullet in the neck. Simple logic. Did anyone read the brass properties from Copper.org. Stress relaxes with time.
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Temperature plays a role in it. Brass, like most things, expands and contracts with temperature change. If you load your ammo at home in a nice warm environment, then take it out to the range in 40 degree weather, that brass is going to move, along with a change in the "neck tension".
Interesting. Have you ever measured this change? I load in a 68° room and then shoot when it's in the 20° range. (not now, thankfully)
Would you expect to see a difference? I wonder how the caliper or mike reading is changed with a 50° change as their surfaces are also expanding and contracting.
dmoran
Donovan Moran
@fguffey
The word "tension" means "state of being stretched". So when people are talking about "neck tension" we are referring to a measured amount of tension of the neck on the bullet, in inches.
Example:
0.267" = measured neck diameter after sizing, but before seating a bullet
0.269" =measured neck diameter after the bullet is seated
0.002" = the difference, and the amount of measured neck tension
Now @fguffey try to comprehend measuring tension in inches without getting mad and ranting on the internet so you won't get worse confused. Then you to could refer to how much you size down the neck in relationship to its stretched measurement of the loaded round when someone ask you instead of getting all mad and goofy on the internet. But as is, you appear to be the only one, who can't comprehend the measurable reference simplicity...
BoydAllen
Gold $$ Contributor
I have seen the increase when temperature could not have been a factor. Try this. Size part of an otherwise identical set of fired brass, leaving some unsized, then, two weeks later size the rest of it, and load it all, seating bullets with an arbor press and die that is designed for the press. You will easily be able to feel the difference in seating force. All of this you would think, and it stands to reason stuff is not worth one simple test. We may not know the exact mechanism by which this takes place, but it does. The only doubters are those that have not done the test. One additional test that I have not done is to measure the necks right after sizing and after some time has gone by. If someone has done that, I would like to hear what your results were.
Alex Wheeler
Site $$ Sponsor
Your correct. Stress does relax with time. But thats internal stresses in the metal, not the metals hardness, yield, or tensile strength. Not that it really matters why the seating force increases. All that matters is it does, and that we learn how it effects our shooting.
dellet
Gold $$ Contributor
Since most metals basically have a memory, in that they try to return to a previous shape when cold shaped, and stay when shaped hot.
Why wouldn't a fire formed neck actually want to expand back to the previous diameter it was cold formed from, instead of shrink back to the cold formed size?
This seems to open the question of different results depending on if the neck was sized internally with a ball, or externally with a bushing?
Why wouldn't a fire formed neck actually want to expand back to the previous diameter it was cold formed from, instead of shrink back to the cold formed size?
This seems to open the question of different results depending on if the neck was sized internally with a ball, or externally with a bushing?
I have taken my Wilson seater and final seated the bullet just before shooting each .
I never see a improvement on target if anything it was not as good . It could be what I was seeing was the condition was changing and I didn't see it . No change in ES . Larry
I never see a improvement on target if anything it was not as good . It could be what I was seeing was the condition was changing and I didn't see it . No change in ES . Larry
Loading at the range in the shade, no matter the ambient temperature, then moving that loaded brass into direct sunlight, which is much warmer, is going to cause a change in that brass. We quickly realize how comforting moving from direct sunlight to a shady area can be. Ten or fifteen minutes in the sun is going to affect that brass.
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