.308 neck tension

[fguffey]

I don't think 243winxb was advocating using the die-sans-expander to load. He was simply suggesting a test to see what was going on with each step of the sizing process.

I suggest measuring before and again after.

F. Guffey

 

[fguffey]

it measures outward tension to the barrel.

You can not help yourself; I have no infatuation with tension, if it measures tensions I want to know how many tensions.

F. Guffey

 

[dmoran]

You can not help yourself; I have no infatuation with tension, if it measures tensions I want to know how many tensions.

F. Guffey

Click Here: www.saami.org/glossary

 

[dmoran]

You want to measure bullet hold

F. Guffey

 

[retired]

stop that,
it is just not fair bring facts into a discussion.

View attachment 1044119

 

[Bart B.]

I have no infatuation with tension, if it measures tensions I want to know how many tensions.

Trillions, at least.

One for every place and force angle you can possibly measure where a case neck molecule touches a bullet molecule. Use a scanning electron microscope to see and count them.

Then subtract one for the human tension (mental stress) the person that doesn't understand it who is trying to measure it.

 

[Bart B.]

Neck tension has several meanings....... Other times by the force needed to push the bullet out of the case neck.

SAAMI says it's very close to that:


Extract means push it out with pressure in the case.

Or, pull it out with a collet gripping it with the tension in pounds on the bullets indicated on a gauge dial.

 

[josebd]

I'm using lapua brass, inside measurement after full length resizing with foster die,.304
I have been reading up on the Sinclair mandrels,any suggestion if I should try it? Do I really need less tension? The worst runout I get after seating bullet is .004

ok,inside measurement is .304 after fl resizing,and I have with bullet seated .001 neck tension with lapua brass and .002 with nosler brass
so it would be better if I get a sinclair expander die that resizes to .307 or .306 ?

 

[Bart B.]

What is the bullet diameter?

The sized case neck inside diameter should be no more than .001" to .002" smaller.

How thick are the case check walls? .012"? .014"?

 

[fatelvis]

You can not help yourself; I have no infatuation with tension, if it measures tensions I want to know how many tensions.

F. Guffey

I admit, I’m a little infatuated with tensions. I lead a sad, simple life.

 

[josebd]

What is the bullet diameter?

The sized case neck inside diameter should be no more than .001" to .002" smaller.

How thick are the case check walls? .012"? .014"?

.308

 

[avidflyer]

ok,inside measurement is .304 after fl resizing,and I have with bullet seated .001 neck tension with lapua brass and .002 with nosler brass
so it would be better if I get a sinclair expander die that resizes to .307 or .306 ?

If you have 304 after sizing you have at least 4k neck tension with a 308. I use a plug gauge (can buy cheap from amazon) to see where I'm at on a sized case. some fl size them set tension with a expander.. works great just an extra step

 

[Bart B.]

With bullets ..308" diameter, resized case mouths should be no smaller than .306" and .3070" or .3075" is usually best for accuracy.

Bullets go into case necks, not onto (around?) them like a candy Lifesaver would. It's the neck inside diameter that's critical for gripping the bullet.

 

[josebd]

Pm sent bart b

 

[fguffey]

pull it out with a collet gripping it with the tension in pounds on the bullets indicated on a gauge dial.

They did not mark the dial on the indicator to read tensions, the dial reads pounds. A reloader with a few shop skills can push the bullet out of the case, he can not measure tensions because no manufacturer makes a gage that measures tension, they do make a deflection gage, but, it also measures deflections in pounds and in thousandths.

Reminds me of case head space, SAAMI does not list case head space in their drawings of cases, they do not include the symbol for head space in their case drawings. And then came the Internet, Internet reloaders talked themselves into corners because they had gigs of space used up on subjects they could not get do-overs.

F. Guffey

 

[Bart B.]

They did not mark the dial on the indicator to read tensions, the dial reads pounds. A reloader with a few shop skills can push the bullet out of the case, he can not measure tensions because no manufacturer makes a gage that measures tension, they do make a deflection gage, but, it also measures deflections in pounds and in thousandths.

Reminds me of case head space, SAAMI does not list case head space in their drawings of cases, they do not include the symbol for head space in their case drawings. And then came the Internet, Internet reloaders talked themselves into corners because they had gigs of space used up on subjects they could not get do-overs.

Amazing. Simply amazing. Unbelievably amazing.

That happens when someone is in a maze.

I used to be in one. Most of us were at one time. Then someone gave me 25 cents and I bought my way out of that maze. Should I mail you two bits? You, too, can be a 2 bit operator.

 

[Jackal2016]

They did not mark the dial on the indicator to read tensions, the dial reads pounds. A reloader with a few shop skills can push the bullet out of the case, he can not measure tensions because no manufacturer makes a gage that measures tension, they do make a deflection gage, but, it also measures deflections in pounds and in thousandths.

Reminds me of case head space, SAAMI does not list case head space in their drawings of cases, they do not include the symbol for head space in their case drawings. And then came the Internet, Internet reloaders talked themselves into corners because they had gigs of space used up on subjects they could not get do-overs.

F. Guffey

Umm, ...the SAAMI drawings of cartridges and chambers that I have looked at do have headspace dimensions indicated on them.

 

[L W P]

I'm not sure which size bushing you are using? I've had great luck with .335" bushing using Lapua 308 brass that has not been turned. A .334" bushing has worked for brass that has been neck turned a little so as to make the necks uniform. Also I am using the Redding F/L bushing die with the expander ball in it. It just barely kisses the inside neck on its way out.

 

[Bart B.]

Umm, ...the SAAMI drawings of cartridges and chambers that I have looked at do have headspace dimensions indicated on them.

The SAAMI rep I discussed this with some years ago agreed. They've not put it in their glossary but it's akin to headspace on rimless bottleneck headspace gauges; head to shoulder reference diameter measurements. Translates to rimmed and belted cases easily for their shoulders position relative to their head. Seems very simple and straightforward to 99.99% of us.

Full length sizing dies for such cases have headspace too. Typically .005" less than GO chamber headspace gauges. Drop a GO gauge in a die then measure how much its head sticks out. Compare the measurement to the standard shell holder .125" base to flat dimension.

 

[divingin]

They did not mark the dial on the indicator to read tensions, the dial reads pounds. A reloader with a few shop skills can push the bullet out of the case, he can not measure tensions because no manufacturer makes a gage that measures tension,

[Rant on, sorry, guys]
Ever get on a bathroom scale? How many weights are you? Or are you stepping on the scale to pound yourself?

Come on, Guffey, terms are not the end-all/be-all. Neck Tension is term that refers to the stasis of the interference fit of the bullet in the somewhat smaller case mouth. That tension (or rather, the force needed to overcome it) can be measure in pounds, ounces, kilograms (or fractions thereof, if desired), whatever you set your scale to read.

Everyone on here knows what the term is and why it's being investigated. Why you feel the need to say it's nonsense baffles me (and apparently, a lot of others.) If you don't like the term, and would prefer to use a different term, write a macro that changes the term to one you prefer (or ignore posts asking about it altogether.)