Question on Neck Tension

[Grover64]

Looking for some clarification on neck tension. When your ID (inside diameter) with a pin gauge is .223 would that be considered one thousands or two thousands as your working with a cylindrical measurement?

 

[Bill Norris]

Looking for some clarification on neck tension. When your ID (inside diameter) with a pin gauge is .223 would that be considered one thousands or two thousands as your working with a cylindrical measurement?

Since you are measuring across the opening and not including the case wall it would be .001

 

[Grover64]

But regards to tension as when measured OD outside diameter of case is .248 with and inside diameter of case is .223. So after seating the bullet .224 the outside diameter of case measures .250. after bullet seated. So would that mean 0.002 tension?

 

[RegionRat]

"tension" and "neck tension" terminology on forums is an informal term.
The general term means difference on the diameter, so for the example of a 0.224 bullet into a 0.223" neck that would mean 0.001" "tension" or "neck tension".

 

[Grover64]

"tension" and "neck tension" terminology on forums is an informal term.
The general term means difference on the diameter, so for the example of a 0.224 bullet into a 0.223" neck that would mean 0.001" "tension" or "neck tension".

Thanks Fellas

 

[64Rambler]

But regards to tension as when measured OD outside diameter of case is .248 with and inside diameter of case is .223. So after seating the bullet .224 the outside diameter of case measures .250. after bullet seated. So would that mean 0.002 tension?

Yes. That's 2 thousandths. Be careful with gauge pins; it matters if it's a plus (+) or a minus (-) pin, plus, they are very sensitive to the most minor surface imperfections, like a "dirty" case neck. If your 0.223" was a (+) pin in a fired neck that had some carbon or a scratch, that might explain why that method is giving you 0.001", but measuring the OD of the neck before and after bullet seating is giving you 0.002".

 

[Bill Norris]

Yes. That's 2 thousandths. Be careful with gauge pins; it matters if it's a plus (+) or a minus (-) pin, plus, they are very sensitive to the most minor surface imperfections, like a "dirty" case neck. If your 0.223" was a (+) pin in a fired neck that had some carbon or a scratch, that might explain why that method is giving you 0.001", but measuring the OD of the neck before and after bullet seating is giving you 0.002".

Correct. That is two different measurements.

 

[L.Sherm]

Brush your neck with a stiff nylon brush before you use a pin guage to measure inside of necks.

 

[JFrank]

The way it was introduced to me is about as simple as pie.
Measure the loaded round OD followed by the resized OD.
The difference is the amount of bullet hold applied .

 

[Tommie]

Paging Mr. Guffey

 

[Retired shooter]

Easier to think of it as " press fit". The difference between the ID of the case neck, and the OD of the bullet.

At least that's the way I learned, years ago in the machining business

To all a good evening.

 

[Tesoro]

I like to over complicate neck tension by looking at it as a multi function of how much the neck is expanded by 'press fit' along with how even the neck thickness is, how thick the neck wall is, what brand of brass it is, how many times it has been worked before annealing and how much of the neck is in contact with the bullet. lol.