I'm getting ready to send my new Redding FL sizing die to Redding to have them open up the neck a skootch. Normally for tactical shooting I like .001" to .002" neck tension.

This rifle is going to Alaska for Grizzly. The action will be a Pre 64 M70 with the focus on 250 gr Accubonds, first.

How much neck tension would you suggest in a rifle like this? Something which will give me long case life but not let the bullet seat deeper upon recoil.

Thanks,

Alan

On a "hunting" rifle .003. Consistancy has more affect on accuracy than the amount of neck tension

GSSP,

I use standard "Group D" RCBS dies when loading my Sako 75, in 9.3 x 62. ID of my re-sized brass is .360. I full length re-size my brass. I prefer increased neck tension and on most of my hunting loads. I load near or just over SAAMI OAL's. I do not want the problem of the round being to long for the magazine, and I do not want a problem with closing a bolt. I check every round after it is resized to be sure the bolt will close. I do not use a crimp die.
I usually take some 600 grit steel wool or some flitz polish and polish the decapping/sizing button in order to increase neck tension just a smidge.
My go to load is Norma Brass, 250 gr. accubonds, 58 gr. varget, Fed 210M primers and 3.290 OAL.

If you are concerned about case life, reduce your loads from book max and anneal your cases after a couple firings.

Here's mine.
Best,
GWB




PS:
I think the rifle and what it likes will have more of an effect on accuracy than neck tension.

quote:

Originally posted by D Humbarger:
Consistancy has more affect on accuracy than the amount of neck tension

Exactly, and very low neck tension is hard to get consistent unless you are prepared to do additional case preparation such as outside neck turning or annealing. Outside neck turning will not increase your case life if your (factory?) chamber has a large neck diameter. Case annealing may help in terms of case life.

Without special case preparation, I personally prefer .003 - .005 neck tension on hunting rounds, with netto .004 often chosen. (Netto: after brass springback).

- mike

GSSP is you want longer case life take that expander ball out of the die. Do not use it. Why work the case neck TWICE? Have Redding size the neck of the sizing die to give the tension that you want without useing the expander. (an old bench rest techinque)

Ah ha! Some one finally caught on to what I was looking for. No one that I know of makes a bushing die in 9.3x62.

Besides, if I use the die as is I'd only get .0025" neck tension.


New, sized case = .3785”
New, sized and expanded case = .384”
New, sized, expanded with 250 gr Nosler Accubond bullet seated = .3865”


Alan

Gone shooting for the next few hours

quote:

How much neck tension would you suggest in a rifle like this?

Neck grip is significantly less than what many presume it to be no matter how small the hole is before the bullet is seated. And it matters not if we expand a neck part way up in the die, the controlling factor is that the bullet itself will be the final "expander."

"250 Nosler Accubond bullet seated = .3865”

You're part way there. Now, pull the bullet and see how much spring back you have; whatever the difference is, that's your real "tension". All any higher "bullet tension" increases is run out.

It'll likely be about 1 thou because any greater inside difference simply exceeds the elastic limits of the brass and permanetly stretches it. So, the typical pulled bullet .001", +/-, residual difference is all you gonna end up with no matter how small you leave the neck inside diameter before seating.

Jim,

Thanks for the suggestions. I'll check measurements you mentioned; not only with my 9.3x62 but with a 257 Roberts I have where I just got a FL sizing die back from Forster after they honed it out a bit for me.

I'll report back what I find.

Alan

PS. Longer brass life and reduced bullet run out is what I'm looking for.

quote:

Originally posted by Jim C. <><:

quote:

How much neck tension would you suggest in a rifle like this?

Neck grip is significantly less than what many presume it to be no matter how small the hole is before the bullet is seated. And it matters not if we expand a neck part way up in the die, the controlling factor is that the bullet itself will be the final "expander."

"250 Nosler Accubond bullet seated = .3865”

You're part way there. Now, pull the bullet and see how much spring back you have; whatever the difference is, that's your real "tension". All any higher "bullet tension" increases is run out.

It'll likely be about 1 thou because any greater inside difference simply exceeds the elastic limits of the brass and permanetly stretches it. So, the typical pulled bullet .001", +/-, residual difference is all you gonna end up with no matter how small you leave the neck inside diameter before seating.

This is a darn good post!

quote:

This is a darn good post!

Thanks Vapors. Coming from you, that's a lot.

You can't know how often I've planned to make a posting but didn't because you got there ahead of me!

Jim,

Sorry for the delayed response. Realized I didn't have a 9.3mm RCBS bullet puller collet. Finally decided to simply use a pair of pliers and and old press to pull the bullet. Here are the measurements.

New, unfired Lapua 9.3x62 brass.

Loaded with Nosler 250 Accubond = .3865" at neck
Pulled = .385" at neck

That means it only had .0015" neck tension.

Alan