Neco tool questions.

[lurcher]

Wow thanks guys all of these recent replies are WAY beyond my level of experience but there's lots of interesting stuff there to try out.

Are you using wilson seaters mike? I have one wilson seater that was made using a blank and chamber reamer. I have had issues with brass not fitting in it that I thought was possibly due to a partially sized neck as I could not sort the problem by sizing the brass with a redding body die. With these partially sized necks do you run into issues with brass not entering seaters, have you modified your seaters in any way?

 

[mikecr]

The changes that I spoke of were significant, form in the middle of the pack or lower, to competitive

This is my basis for seating being different than tuning. Seating seems to me more like an 'issue'.
3thou seating adjustment, really didn't change neck tension, case capacity, or muzzle velocity. It didn't affect the parameters of tuning. Yet it can screw things up beyond any of those tuning parameters.
It is common for seating adjustments alone to take a gun from twice as bad to twice as good, and no amount of any other adjustment can do that.
Seriously, I could take a true 1/2moa gun, throw 5 to 10gr powder adjustments at it, and never see it extend all the way to 1.5moa grouping. It'll get ugly, but not THAT ugly.
But I can reach 1.5moa grouping easily, or possibly improve it to 3/8moa, with a minor seating adjustment. This is no more tuning IMO, than fixing a bedding issue.

lurcher, I do use Wilson seaters.
2 were cut with my reamers. Others were fine as is.
If your cases don't fit a seater well, but actually chamber well, I would get the seater honed a bit. Maybe JLC does this as well. I haven't run into that issue.
If the cases neither fit the seater or chamber well, it goes back to the qualifiers I mentioned earlier, or there is some mismatch that needs to be fixed on the sizing side of it.

 

[lurcher]

Over time, the brass bucks a bit of it. So while I recheck HS, I recheck seating force from the necks

One last question Mike. How are you measuring seating force? just by feel using an arbor press, a K&M press with a dial indicator? (I have one of these but can't say I have developed much confidence in the dial reading side of it yet) or some other way?

Also here's another take on the partial neck sizing body bump versus FL size full neck size debate, what do you make of this? What happens here jam versus jump

 

[BoydAllen]

mikecr,
For those of us who tune that way, it is just another tool, like powder weight (or volume),and neck tension. At a short range benchrest match, if your rifle is not shooting up to how you think it should, given conditions, previous performance, and how you think you are driving it, a change will generally be made, and I have heard more regrets from waiting too long to make it, than from making a move too soon. By taking several loads to the line, Mr. Boyer can test them on the sighter, before starting his record group, and then choose the one that seems to be the best for the conditions in that match. If it was science, he should be able to look at the temp., humidity, possibly air density, go to his book, and find the right load, for that particular 5 shot group. Tuning has some science, but it is mostly an art....that I wish I was better at. My friends that were too tightly tied to a previously determined seating depth suffered for it. Often, it's not about trying harder (what they had been doing) but doing something different, and having the experience to pick the right thing to do.
Boyd

 

[bozo699]

Mike, Boyd,
I am headed for my 1K shoot this weekend, I implemented as much of your advice as I could, I put my f/l sizer up, used the body die and only neck sized just over 1/2 bullet diameter, about .132 I have the powder charged to the kernel. Base to ogive just cant get any better, I think partial neck sizing did help with consistent seating depth My rifle is very picky on seating depth, you can literally see your groups shrink and then grow again as you change it. I thank the two of you for all the advice. Mike I don't understand your last couple of post I would like to discuss them as I obviously am missing something on the seating depth part of your posts, to me it sound like seating depth has nothing to do with tuning and in the same post it sounds like your saying it can have the most effect on group sizes, I know I must not be interpreting it correctly. I will pop in and ask a few questions when I get back from the shoot, I'll have my smart phone with me but it's not easy to use, thanks again.
Wayne.

 

[mikecr]

How are you measuring seating force? just by feel using an arbor press, a K&M press with a dial indicator (I have one of these but can't say I have developed much confidence in the dial reading side of it yet) or some other way??

I use a similar method to K&Ms. But instead of mechanical belleville washers/indicator, I use a resistive loadcell built into a Sinclair expander die, and measured/reading with a basic meter that I built.
I can also graph seating force by neck in a spreadsheet, but I don't.
Currently working on another device to measure actual tension.

Also here's another take on the partial neck sizing body bump versus FL size full neck size debate, what do you make of this? What happens here jam versus jump

NOTE THIS(at the end of the discussion): "I place a high value on easy bolt operation and true full length sizing helps that quite a bit"
This I suspect is the basis from which all rationalizations about FL sizing stem -from competitors.
They do need easy bolt turn, as it helps them group shoot better. They also tend to migrate to faster powders, running higher pressures, for better grouping. This locks them into FL sizing anyway, but is often twisted into a validation that it is the FL sizing itself that is providing for better grouping..
Really, how would they know?
Notice how the discussion goes roundy roundy, earlier supporting partial neck sizing, only to cave into FL sizing that he's forced to do anyway -to be competitive. Then, he recognizes banana cases and boltface support as contributors to misalignment, while proposing that FL sizing(that caused his bananas) is a major part of the fix..

As far as jam/jump to FL sizing & alignment? Well, like the man said, your throat is the fulcrum either way. And jamming bullets wouldn't seem(to me) to provide for better alignment than a tiny jump engraving on firing. Some chamber/bullet combos provide better accuracy with jumping, some jammed. So I don't consider jamming as a standard, much less an accuracy enhancing approach.
I don't think jamming aligns anything FL sizing or not, because chances are the chambered bullet is against the throat.
I believe it was Vaughn who analyzed inconsistent tension on chambered cartridges as bad for precision. I beleive this, and that's why I put efforts into making STRAIGHT ammo rather than tricking myself into believing that concentric ammo, however crooked, is a valid goal.
Jamming, realistically, would produce more tension, with crooked ammo, unless you had truly huge clearances.

I wouldn't suggest that perfectly fit, aligned, powder weighed, capacity matched ammo would shoot better than horribly sloppy ammo, because I've never seen it proven one way or another.
I think we should all leave it at that, while trying to improve, and maybe gain understanding down the road that advances shooting for everyone. THis, rather than rationalizing what is(or seems) as the best that will ever be..
Does anyone really believe that what is commonly done today -is the best it can be?
C'mon

 

[BoydAllen]

Mike,
You are involved in some very interesting research. I would love to have a consistent way to look at seating force and bullet pull. Having said all that, let me disabuse you of the idea that banana shaped cases are an inevitable result of FL sizing. I have Hornady's cheapest one piece die, in 6PPC. I have used it to size many cases that have been FL sized with another die, that moves the brass about .0005 a little in front of the extractor groove, not at all in diameter at the shoulder, and is usually set to bump shoulders .001. Using a Sinclair (four ball support style) concentricity gauge, the runout at the end of the necks, of cases sized in the Hornady die, is something like a third of a thousandth. I can live with that. As for the bushing die, when I use it like a body die (no bushing) the cases come out as straight as they went in, and my recent experience with a carbide bushing (ground, much straighter) has shown me that the major reason that cases from this die have, in the past, been a little less straight than I would have liked (loaded rounds still at about .00015 on the bullet) is almost entirely because of steel bushing (bot coated and uncoated) quality, or rather lack of it. On a tangent, going to thinner necks, to increase neck clearance, has given me to reason to press a previously untried .256 Wilson Bushing into service, and I am very pleased to report that it gives splendid results, much better than any previous non-carbide bushing. Pure luck...

 

[mikecr]

When I talk down on FL sizing it's with a more or less 'sloppy sizing' perspective. Afterall, this is what most are left with using mismatched off the shelf dies with their chambers. Most do not even measure their brass to understand sizing.
Their runout numbers are not like mine or yours.

If most reloaders sized like you, and measured results, there would be far fewer issues constantly brought up in forum reloading sections.

My next neck tension measurement tool will be a hydraulic expander with pressure indicating at 1thou of expansion(which will springback). It will be caveman proof when I can take away no more.