Case Neck Thickness Variation

[Mikecr]

Assuming you would have the desired thickness left, would you turn cases with only .0005" variance?

I do turn most of my cartridges, but for the few I don't, I just use thickness variance culled cases.
If my unturned target thickness(for clearance) is .012 then I would accept .0122x-.0118x as measured with a ball mic, mid-necks.

But there is no reason to consider what you'll do with .0005" while you're not reading it correctly to begin.
The Redding tool won't work any better than with a pin or cylinder anvil on a mic.
You need a ball anvil, with a stop, or you're not reading neck thickness properly.

 

[Deleted member 46119]

About how long would it take you to turn 200 cases from say .0165" to .0145"?

I use a Forster. So an hour or two.

 

[jrock]

What's the dial gauge for the redding tool?

The Redding tool measures in 0.001" increments. I went with it because I wanted to have more consistent brass and I don't bench shoot. This site has some good comparisons Tools for Measuring Case Neckwalls

 

[bill123]

The Redding tool measures in 0.001" increments. I went with it because I wanted to have more consistent brass and I don't bench shoot. This site has some good comparisons Tools for Measuring Case Neckwalls

That site and the following quote from the article:

"When turned and unturned necks were checked first on the Redding tool and then double-checked with a Starrett ball mic, the results were the same–but of course the Redding Gauge can sort multiple cases more quickly."


sold me on the Redding tool but it sounds like it might have been a mistake? Did you put a .0001" dial gauge on your Redding tool? From what others have said, it sounds like the Redding tool isn't any good.

I'm trying to get into the neck thickness stuff slowly. I was hoping to see an increase in precision by first sorting brass by thickness variation and then possibly getting into turning. I'm still wondering if just sorting brass by neck thickness / variation will give a noticeable improvement to precision.

My thinking is that if I just start this process by buying a bunch of turning equipment and turning all of my brass to the same thickness, I'll never completely understand the benefit of the intermediate steps. I'll go from mediocre brass to great brass without the benefit of the learning process.

 

[Canadian Bushman]

Neck turning isnt gonna make or break your load. Its simply controlling one more variable in the process.

My number 1 reason for neck turning was to precisely control the amount i work the necks on my brass. This helped me better control the amount of neck tension i was using, and greatly increased the consistency of my feel at the press.

The more consistency you can bring into ALL aspects of your reloading process the more accuracy you will be able to produce.

 

[bill123]

Neck turning isnt gonna make or break your load. Its simply controlling one more variable in the process.

My number 1 reason for neck turning was to precisely control the amount i work the necks on my brass. This helped me better control the amount of neck tension i was using, and greatly increased the consistency of my feel at the press.

The more consistency you can bring into ALL aspects of your reloading process the more accuracy you will be able to produce.

So you wouldn't necessarily be able to quantify the difference, for instance attributing 1/8 minute tighter groups at longer distance because you turned?

 

[Canadian Bushman]

Nope. Not solely from neck turning.

Neck turning allowed me to better utilize my neck bushing set up with better control over neck tension, neck size, bullet run out, and consistency between lots of ammo. If anything i feel this has reduced flyers and helped me keep a tighter velocity spread, but my 1/2 moa rifle still shoots a 1/2 moa.

 

[Canadian Bushman]

I dont think ive ever shot accurately enough to judge an 1/8th moa. Every now and again ill pile a few up in a 1/4, and thats not real often. Im just not that good at shooting or reloading.

 

[bill123]

I dont think ive ever shot accurately enough to judge an 1/8th moa. Every now and again ill pile a few up in a 1/4, and thats not real often. Im just not that good at shooting or reloading.

I'm not either, just using 1/8 as an example. I guess my real goal in all of this is to remove as many sources of error as possible so when I shoot a bad group, I know that it's something I did that I need to work on.

 

[flashhole]

Some really good banter in this thread. I wish they had a "Like" button.

Yes, you take baby steps towards consistency and repeatability to eliminate variables. In the end it's the best way to improve shooting skills.

 

[bill123]

Some really good banter in this thread. I wish they had a "Like" button.

Yes, you take baby steps towards consistency and repeatability to eliminate variables. In the end it's the best way to improve shooting skills.

I agree. Great discussion. I learned a great deal. Thanks for all of your input.

 

[Mikecr]

Bill123 you're right. You should learn your way through intermediate steps.

Cylinder(pin, tubing, etc) anvils don't work well for cartridge necks because of inherent donuts present.
All new cases have donuts from their manufacture. Case thickness drops from webs all the way to mouths. So necks are thicker near shoulders than they are near mouths. This is why a stop is so important.
Now with a pin resting against one internal side of a neck that varies in thickness, you can end up with 2 contact points and a gap between them, or not.. If the neck is held on axis in this condition you can end up with solid contact at the thickest point, with the rest of the neck swinging in about .0005" of wind. When you combine this with sections of neck that aren't straight anyway, you end up with more abstract than accurate measure.
With turned necks every measure gets easier and better, but the donut is still there until fire formed out, or reamed out.

A ball anvil removes these abstracts by taking measure to a tiny point. If you were to replace the anvil/pilot on your Redding with a ball anvil, you would have a faster ball mic(only with a dial)(great improvement).
The article referenced is just an article, and it's full of mistakes as many magazine articles are. They lack peer review.
This is what RIGHT looks like:

 

[bill123]

Mike. Who makes that gauge? Does the stop come with it or did you add it?

 

[Mikecr]

Sinclair Digital Case Neck Micrometer | Sinclair Intl
I made and installed the stop easy enough.