Neck tension on Fire Formed Brass

07 September 2008, 23:31

thor45

Guys,
I'm new to reloading and new to the forum, and seeking some education.

Working up a hunting load for my 300 win mag (73 to 76 grain RL22, Nos. Brass, WLRM primer, Nos. 180 gr. partition).

Anyway, I've noticed that my neck tension when seating fire formed brass is tighter than compared to new brass. I'm looking forward to the learnign process and thankful that forums like this exist.

Brent

07 September 2008, 23:53

Fish30114

Brent, that can often be the case. Dies vary slightly, and when resizing, the neck can very easily be constricted by your die to a tighter inside diameter dimension than your original brass.

(I am assuming you mean that you notice this when seating bullets in your newly sized fire formed brass vs your original reloads.)

This should not be an issue. It is a pretty advanced reloading stage, and many (including me) feel that really tinkering with neck tension, unless yours is too loose, is a technique best left for benchrest rigs.

Having said that, if you want to control your neck tension precisely, then you can purchase bushing sizing dies, and precisely control how much your neck is squeezed down during sizing--you can even go to neck sizing only, until your cases have swollen too much to chamber properly, in which case you would use a body die, sizing only the body, possibly bumping the shoulder back, and then neck sizing your brass--all this and then you can look into 'neck turning' your brass, basically trimming the thickness of your cases in the neck area only! This is a quick synopsis and again all this is advanced stage reloading stuff, and IMO is mostly overkill for hunting ammo....

But I do own a few neck sizing, body and shoulder bump dies

Unless your seating process causes a neck to crumple, you should have no issues--in fact some folks think higher neck tension in hunting loads is a good thing, including me.

Good luck, and welcome to AR!

08 September 2008, 06:57

thor45

Thanks Fish,

I use a FL sizing die with a busing, so I should have consistent neck tension, then an inline seater. But my original reloads where with new brass which I did run through the die, and it is noticeable when seating on my fire formed brass. I appreciate the information.

The irony in this experience for me is that at each different powder charge my group is more than acceptable and I'm splitting hairs searching for the tighest group...when the vitals of the elk are as big as the entire target I'm using. But it sure is relaxing and fun tinkering.

08 September 2008, 07:08

Fish30114

quote:
Originally posted by thor45:
The irony in this experience for me is that at each different powder charge my group is more than acceptable and I'm splitting hairs searching for the tighest group...when the vitals of the elk are as big as the entire target I'm using. But it sure is relaxing and fun tinkering.

That's for sure! It's also a real confidence builder to know how capable your rig really is!

08 September 2008, 07:53

N. Garrett

Brent,

When you fire a cartridge, and eject the empty case, can you slip a bullet into the neck easily (before resizing) ?

If the bullet doesn't slip in easily, you may have some increased thickness of the brass at the neck.

Garrett

08 September 2008, 08:25

woods

quote:
Originally posted by Fish30114:
Brent, that can often be the case. Dies vary slightly, and when resizing, the neck can very easily be constricted by your die to a tighter inside diameter dimension than your original brass.

(I am assuming you mean that you notice this when seating bullets in your newly sized fire formed brass vs your original reloads.)

This should not be an issue. It is a pretty advanced reloading stage, and many (including me) feel that really tinkering with neck tension, unless yours is too loose, is a technique best left for benchrest rigs.

Having said that, if you want to control your neck tension precisely, then you can purchase bushing sizing dies, and precisely control how much your neck is squeezed down during sizing--you can even go to neck sizing only, until your cases have swollen too much to chamber properly, in which case you would use a body die, sizing only the body, possibly bumping the shoulder back, and then neck sizing your brass--all this and then you can look into 'neck turning' your brass, basically trimming the thickness of your cases in the neck area only! This is a quick synopsis and again all this is advanced stage reloading stuff, and IMO is mostly overkill for hunting ammo....

But I do own a few neck sizing, body and shoulder bump dies

Unless your seating process causes a neck to crumple, you should have no issues--in fact some folks think higher neck tension in hunting loads is a good thing, including me.

Good luck, and welcome to AR!

+1 with one caveat, more neck tension or a more severe bullet grip often leads to increased runout. One of the reasons why the Lee Collet Neck Sizer produces very little runout is that it resizes the inside of the neck diameter .001" to .002" below caliber. When ordering smaller mandrels from them I was warned about this and found it to be true.

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08 September 2008, 19:20

thor45

Garret I will check the fired brass after my next range session.
Thanks
Brent

08 September 2008, 21:43

Jim C. <><

quote:
I've noticed that my neck tension when seating fire formed brass is tighter than compared to new brass.

Try running a new case through your sizer die before loading it. Suspect you will find the tension matches fired cases pretty close then.

You can be sure that your bullets will drop into a once fired case easily. It takes several resizing cycles to push shoulder brass into necks.