Neck Tension

Bushmaster · Posted: Thu Sep 13, 2012 7:48 am Post subject: Re: Neck Tension

That one, Omni, might be that the resized cases that were set aside for a monthor two have [due to elasticity] slowly returned to near original dimensions.

Popcorn

Aloysius · Posted: Thu Sep 13, 2012 10:30 am Post subject: Re: Neck Tension

I got also the impression that brass becomes stiffer and harder by aging. For my Hornet I was presented very old Winchester amno and normally the Winchester 45 grs HP factory round works very good in my Anschütz. But this old Winchester rounds are no good for hunting because often the cases get cracks in the neck (which make that the holes on my target appear about 2" lower than normal at 100m). And even it's a once fired case, it's no good for reloading, because it has already a split neck.

Ominivision1 · Posted: Thu Sep 13, 2012 12:56 pm Post subject: Re: Neck Tension

That is definitely true Aloysius, I've had brass from 40 to 60 years ago that were re sized and some that were not, doesn't matter, all cases cracked after firing! The only way around this is to anneal the neck again, and even then annealing very old cases don't always turn out good.

slimjim · Posted: Thu Sep 13, 2012 6:49 pm Post subject: Re: Neck Tension

Ominivision1 wrote:

So it appears to me, if you load your components immediately after resizing, you will have less neck tension. And if you load cases that have been already resized sitting for a month or so, you will have more neck tension.

OV1, I'll have to think about this some more and figure out how to consider it. The new Nosler Brass I was using was, in fact, probably 10 years old, just never opened. I did reload them about 30 minutes after running them through the sizing die.

slimjim · Posted: Thu Sep 13, 2012 6:51 pm Post subject: Re: Neck Tension

Bushmaster wrote:

That one, Omni, might be that the resized cases that were set aside for a monthor two have [due to elasticity] slowly returned to near original dimensions.

Ok, Bushy. Every case I have resize has come out of the die with a smaller neck than when it went in. Thus, if what you say is the situation, the neck diameter would be bigger. How does neck tension increase if the case neck has a larger diameter?

chambered221 · Posted: Sat Dec 29, 2012 4:00 pm Post subject: Re: Neck Tension

So how did this story end ???

My brass is always tumbled and then I use a brush on the inside of the neck.
When I changed over to a Redding S-die I had the same issue with neck tension. I went with a tighter bushing and started using the expander button.
In my opinion neck thickness .003-.005 are fine for our applications.
Completely uniforming necks for a standard chamber will often lead to other issues.
Be sure to use a ball micrometer when measuring neck thickness. It's the only way to get an accurate reading.

slimjim · Posted: Sat Dec 29, 2012 9:43 pm Post subject: Re: Neck Tension

I did come up with a way to measure the force. It was significantly different going into a new case (like butter in and out) and lever-slamming to pull the bullets out of a sized case that had been once-fired: night and day. there was no way that I was going to be able to use a spring hanging scale to measure the extraction force. I make sure I keep my new cases separate and use fired cases to hunt with.

slimjim · Posted: Fri Jan 11, 2013 9:27 pm Post subject: Re: Neck Tension

I found a force scale that would work with my RCBS Single Stag Press. I had already changed my .270 Win neck resizing button from .300 to .302 to decrease tension. I no longer have to slam the handle to pull a bullet.

Today, I used 150gr VLDs and 140gr Barnes TSX and did a bullet pull test. I only used a couple of cases so this is not a large sample but it demonstrates there is a significant difference. I used Winchester brass and all cases, fired or not, when through the neck sizing button. Here what I found.

New Brass
31 pounds - 150gr VLD
52 pounds - 140gr TSX

Fired Brass
49 pounds - 150gr VLD
65 pounds - 140gr TSX

You can see that the grooves in the TSX increase neck tension. Now imagine how much higher the tension would have been with a .300" bushing with the TSX.

shahidsaif · Rookie Member Joined: Jan 12, 2013 Posts: 3

you are sent the nice post now.

slimjim wrote:

I found a force scale that would work with my RCBS Single Stag Press. I had already changed my .270 Win neck resizing button from .300 to .302 to decrease tension. I no longer have to slam the handle to pull a bullet.

Today, I used 150gr VLDs and 140gr Barnes TSX and did a bullet pull test. I only used a couple of cases so this is not a large sample but it demonstrates there is a significant difference. I used Winchester brass and all cases, fired or not, when through the neck sizing button. Here what I found.

New Brass
31 pounds - 150gr VLD
52 pounds - 140gr TSX

Fired Brass
49 pounds - 150gr VLD
65 pounds - 140gr TSX

You can see that the grooves in the TSX increase neck tension. Now imagine how much higher the tension would have been with a .300" bushing with the TSX.

Elvis · Posted: Fri Jan 11, 2013 11:16 pm Post subject: Re: Neck Tension

?? hmmmmm????

chambered221 · Posted: Sat Jan 12, 2013 9:26 am Post subject: Re: Neck Tension

Elvis wrote:

?? hmmmmm????

Yea !!!

Do we offer up a beer out of the cooler or an interpreter ???

Elvis · Posted: Sat Jan 12, 2013 1:41 pm Post subject: Re: Neck Tension

my thoughts eggzachary.....

Vince · Posted: Sun Jan 13, 2013 7:40 am Post subject: Re: Neck Tension

Wait and see maybe...might be a spammer testing the water...

slimjim · Posted: Sun Jan 13, 2013 8:07 am Post subject: Re: Neck Tension

I provide this valuable information and all you gun nuts can talk about is the spammer!?!?

Chambered might as well be lost again and Elvis can eat feathers!

Vince · Posted: Sun Jan 13, 2013 8:19 am Post subject: Re: Neck Tension

Be interested to see pics of the force scale mate, and how you set it up. I have always relied upon the standard neck sizer that comes with the dies.

I wonder what sort of difference there may be in velocity and POI on the target? Also, what effect this had on accuracy, if any.