Question on neck sizing and tension . . .

[bigedp51]

I'm new to reloading, and very much appreciate the quality of posts in this forum, so I hope this question is relevant to you all.

I'm noticing much more consistency in my neck concentricity (.223 rem) when using a full-length die with a carbide size button (as opposed to just neck sizing). The button in the FL die measures .222, while the expander I have used in the past (when just neck sizing) measures .223, and of course, the expander is much longer, which I expect would leave the necks with even less tension.

Question is, how much neck tension am I looking for? Should I also use the neck expanding mandrel after FL resizing with the carbide button expander?

And, is the only way to really test this to do a series of loads using both, and watch to see when I am starting to build higher pressures with each case prep technique?

Thanks for any insights folks wish to share,
George

1. A neck sizing die does not fully support the case body and will have more neck rouout.

2. At the Whidden custom die website they tell you they get the most concentric ammunition using full length non-bushing dies.
(the case body and case neck are fully supported and aligned.

3. I get the most concentric ammunition using Forster full length benchrest dies with the high mounted floating expander. The expander enters the case neck while the neck is still held and centered in the neck of the die. And this prevent the expander from pulling the necks off center.

4. I get the most neck runout using a Forster bushing bump die because the case body is not supported. And when sizing down the case neck over .004 using a bushing die it can induce neck runout.

Don't tell Redding I put a Forster expander and spindle assembly on a Redding die. A rubber o-ring is under the lock ring that allows the expander to float and self center. This expander has far less drag on the inside of the neck and now produces very concentric sized cases.

NOTE, my expanders are .0025 to .003 smaller on my full length dies for loading semi-autos and have more bullet grip and not crimp. And this is no problem using the Forster benchrest seater dies.

Also I have sized .223/5.56 cases that have been sitting around for months and I use my expander mandrel die just before loading the bullets and this has no effect on neck runout.

 

[WildRose]

Ok, the whole world is pretending, and 'very few people' care about what neck tension is, how it applies, or how to adjust it.
Should I concede to ignorance is bliss from boastings about that in basis?
I don't know, it's a public forum..
But with interest, I could explain neck tension in more detail than mob notions, which I believe will help folks, and maybe you as well.

What works best usually is sticking with the vernacular that has existed since long before this forum.

Neck tension is a simple concept, it's how snugly the neck holds the seated bullet usually it's expressed in terms of the diameter of the case neck vs the diameter of the bullet.

What do I do about neck tension? Until I started reading this forum I never considered it other than when I occasionally noticed that a bullet seated too easily and then felt a bit loose. Working with what I had at the time I'd simply remove my decapping pin in my sizing die and work the neck again and if the bullet still seated loosely measured both it and the bullet to see if my neck was getting too thin or I had a slightly undersized bullet. Whichever measured out of spec was tossed and I moved on.

After upgrading from a lot of over thirty year old equipment this year I started using new dies including factory crimping dies which ensure the exact same tension on every bullet and that one extra step costs me maybe five seconds for each round I load.

I don't have any tight chambers requiring neck turning (so far at least) so KISS still works pretty well.

Since I started doing the factory crimp on both .260 and .300 Rum loads my groups tightened up to a level I've not ever achieved before so it must be working as intended.

Now if I'm loading specific brass for a specific rifle I tend to neck size only for 2-3 rounds and then try the full length sizing on the fourth.

My results are steadily improving and I attribute it to what I've learned on this forum.

Old timers like myself who started loading back in the seventies usually had one book and those of us that were real lucky had a friend who introduced us into the basics of handloading and we have continued to load the same way, most of us anyhow right up to the present.

We're generational leaps and bounds advanced beyond what was available forty years ago in terms of the rapid exchange of information so there's no reason for any of us to stay in the stone age.

When you've been at this for a few decades instead of being stuck on how much you know you begin to realize just how much more there is to learn, especially if you hang around here much.

 

[evnglst]

Thanks to everyone for your thoughts. All good and useful info that is helping me sort through the variables.

OP