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reelxprs
10-09-2013, 06:50 PM
Has anyone ever tried a 30BR no turn neck chamber. I seem to have problems with my neck turning because I keep having different bullet seating tensions. Some seat with little effort and
some seat with more effort. Doesn't this cause a lot speed variations? I have a .330 neck and have turned to have a .328 neck with bullet seated. What am I doing wrong? I have tried sizing
with as small as a .323 neck bushing and large as a .325 bushing.
Any suggestions would be greatly appreciated.
Jeff Fountain

Jerry W
10-09-2013, 07:24 PM
You could always call Ron Hoehn (http://www.benchrest.com/hoehn/) and buy some pre-turned Lapua brass.

Jerry

alinwa
10-09-2013, 07:26 PM
Has anyone ever tried a 30BR no turn neck chamber.

Yes

I seem to have problems with my neck turning because I keep having different bullet seating tensions. Some seat with little effort and
some seat with more effort. Doesn't this cause a lot speed variations?

No

I have a .330 neck and have turned to have a .328 neck with bullet seated. What am I doing wrong?

Dunno, are you turning in stages using a quality tool?

I have tried sizing
with as small as a .323 neck bushing and large as a .325 bushing.
Any suggestions would be greatly appreciated.
Jeff Fountain


Answers in bold

Bill Scheider
10-09-2013, 08:43 PM
Has anyone ever tried a 30BR no turn neck chamber. I seem to have problems with my neck turning because I keep having different bullet seating tensions. Some seat with little effort and
some seat with more effort. Doesn't this cause a lot speed variations? I have a .330 neck and have turned to have a .328 neck with bullet seated. What am I doing wrong? I have tried sizing
with as small as a .323 neck bushing and large as a .325 bushing.
Any suggestions would be greatly appreciated.
Jeff Fountain

Jeff,

Call me so we can talk this through.

Bill Scheider

843-522-3651

Charles E
10-09-2013, 09:39 PM
Has anyone ever tried a 30BR no turn neck chamber. I seem to have problems with my neck turning because I keep having different bullet seating tensions. Some seat with little effort and
some seat with more effort. Doesn't this cause a lot speed variations?

Probably not with "speed." But it is good to have fairly even bullet pull, and if you're jamming the bullet into the lands, seating depth. The light ones are apt to push back.

Here's hw you can test to see if it matters. Get a neck expanding mandrel with a size of, say, .306. Size your brass down, then make one more pass in the press with the mandrel to take the neck interiors up to .306. Now load & shoot. See if it matters.

At some point you're going to have to learn how to turn necks, but the "going down a bit more & expanding up" is a useful technique in any case. It's how I use to prepare ammunition for a 1,000 yard National Championship match...

abintx
10-09-2013, 11:48 PM
Has anyone ever tried a 30BR no turn neck chamber. I seem to have problems with my neck turning because I keep having different bullet seating tensions. Some seat with little effort and some seat with more effort. Doesn't this cause a lot speed variations? I have a .330 neck and have turned to have a .328 neck with bullet seated. What am I doing wrong? I have tried sizing with as small as a .323 neck bushing and large as a .325 bushing. Any suggestions would be greatly appreciated. Jeff Fountain

Consider this:

NECK TENSION versus TIME

For match rounds:

Size ALL cases at the same time.

Load immediately after sizing to reduce neck tension.

The TIME [between neck-sizing operation and bullet seating] can have dramatic effects on neck tension.

When neck tension is very uniform across all your brass, groups shrink. You’ll also see fewer fliers.

Most reloaders control neck tension by using different sized neck bushings.

This affects how firmly the neck grips your bullets.

But TIME OF LOADING is another key variable.

Using a K&M Arbor press equipped with the optional Bullet-Seating Force Gauge, it was determined that over twice as much force was required to seat the bullets which had been neck-sized two weeks before. The dial read-out of seating force for the “older” cases was in the 60s, while the seating force for the recently-neck-sized cases was in the 20s. (These numbers correspond to pounds of force applied to the bullet).

Conclusion: In the two weeks that had elapsed since neck-sizing, the necks continued to get tighter and stiffen.

Source: accurateshooter.com

Charles E
10-10-2013, 08:42 AM
The fly in abintx's post.

Yes, it stands to reason that if cases are charged & the bullet seated a couple weeks after sizing, neck tension may vary.

However, charging and seating the bullet right away, then not *firing* for a couple weeks has the same effect. Someone did another test, where they used a force gauge to pull bullets after loaded rounds had been sitting for a period of time. Same result, there could be variations in the needed force to pull the bullet.

At some point you just have to deal with the root cause, which seems to involve two things: physiclly even necks, and physically identical case springback after sizing.

O course, many of the short range shooters say "don't anneal" -- it's holy writ, by which I mean they read it somewhere. And that does work, more or less, as long as you get the same number of firings & sizings on each case.

...Except a few very successful ones do anneal, esp. with the .30BR. Now I'm not saying you have to add annealing to your repertoire. What I would suggest is you have to test things yourself, in your rifles, with your particular components and techniques. Some "holy writs" will matter, some won't.

And if you change something significantly, guess what, you have to test again. For example, maybe LT-32 likes light neck tension (I don't know, you'll have to test). And if you've been using N-133, which tends to like heavy neck tension, you may find hat uneven pull matters with one, but not the other.

Etc.

SGJennings
10-11-2013, 05:48 AM
Run a case over your expanding mandrel, run it through the loosest 30 BR bushing you have, lube the inside of the neck a bit. seat the bullet you want to use in increments till it is half way in the neck, send it to Dave Kiff and ask that he make a reamer for it, then wait.

Or, just buy brass from any number of brass services. I like P1ZombieKiller over on 6mmBR.com .

Wayne Shaw
10-11-2013, 07:18 AM
At he very least you need to turn the shoulder off the neck once the brass is necked up, or you'll always have the doughnut inside.

Al Nyhus
10-14-2013, 08:56 AM
Depending on how the necks are expanded, the neck i.d.'s can end up funnel shaped. Issues with the neck i.d.'s often show up as varying neck tension. The neck i.d. needs to be round, straight and parallel with the o.d. of the neck. -Al

Charles E
10-14-2013, 10:08 AM
Depending on how the necks are expanded, the neck i.d.'s can end up funnel shaped. Issues with the neck i.d.'s often show up as varying neck tension. The neck i.d. needs to be round, straight and parallel with the o.d. of the neck. -Al

Or you need to use an slight "expander" mandrel as a part of sizing reloading, to keep the i.d. straight. Turret presses are nice...

For a number of years I used a JACO neck turning tool, which as it comes, cuts a slight taper to the neck. These were some of the best-shooting cases I ever made, but if you use one, you really should run the necks over a .306 (or whatever) mandrel after sizing with a bushing-type die, every time. Not mandatory, but probably best.

For those that don't know, the Jaco neck turner was a design by Ferris Pindell, made for sale by T.J. Jackson. Not popular today, but it did cut great necks. It was not a single point tool, a 1/2-inch lathe bit cut the entire neck at once. The usual setup had a .0004 taper with a PPC case, though of course you could adjust it for no taper. I've long believed that either the chamber neck or the case neck should have a very slight taper.

FWIW

Al Nyhus
10-14-2013, 03:01 PM
Or you need to use an slight "expander" mandrel as a part of sizing reloading, to keep the i.d. straight. FWIW

Or size down against an inside mandrel, ala' the Lee collet lash up. :) -Al

virg
10-14-2013, 07:33 PM
Or you need to use an slight "expander" mandrel as a part of sizing reloading, to keep the i.d. straight. Turret presses are nice...

For a number of years I used a JACO neck turning tool, which as it comes, cuts a slight taper to the neck. These were some of the best-shooting cases I ever made, but if you use one, you really should run the necks over a .306 (or whatever) mandrel after sizing with a bushing-type die, every time. Not mandatory, but probably best.

For those that don't know, the Jaco neck turner was a design by Ferris Pindell, made for sale by T.J. Jackson. Not popular today, but it did cut great necks. It was not a single point tool, a 1/2-inch lathe bit cut the entire neck at once. The usual setup had a .0004 taper with a PPC case, though of course you could adjust it for no taper. I've long believed that either the chamber neck or the case neck should have a very slight taper.

FWIW
AJ Walker still has a few JACO neck turners. If interested call him at (512) 836-0203. They're not cheap, but to me they are the "Rolls Royce" of turners.

virg

jackie schmidt
10-14-2013, 09:18 PM
I cannot agree with any option that would recommend not neck turning a 30BR made from a lapua 6BR CASE.

You are moving a lot of metal. in my opinion, there is no way you can displace that much material and expect the necks to retain any semblance of Benchrest Quality.

Learn to turn necks, and do it correctly.

mks
10-15-2013, 09:57 AM
AJ Walker still has a few JACO neck turners. If interested call him at (512) 836-0203. They're not cheap, but to me they are the "Rolls Royce" of turners.

virg

Got any pictures of the JACO?

mks
10-15-2013, 09:58 AM
I've long believed that either the chamber neck or the case neck should have a very slight taper.

FWIW

Why?

mks
10-15-2013, 10:08 AM
I cannot agree with any option that would recommend not neck turning a 30BR made from a lapua 6BR CASE.

You are moving a lot of metal. in my opinion, there is no way you can displace that much material and expect the necks to retain any semblance of Benchrest Quality.

Learn to turn necks, and do it correctly.

With the springback being different on the thick base of the neck and the thin top, I wonder if the best way of turning necks is to single point them on the outside while the inside is supported on a full-length mandrel. Alternatively, you could use a reamer and an outside collet, but the setup would be more difficult. Your thoughts, Jackie? I think I already know your answer.

I have had less than stellar results with K&M. It seems sensitive to temperature.

Thanks,
Keith

SGJennings
10-15-2013, 11:28 AM
Lay the tuner on a gallon ziplock bag of ice in between cases. Or, if you are really hard over about it, rest it in a bucket of ice water between.

I have used both, but no longer do. The pumpkin stays cool enough as long as I lube well and keep the speed slow.

GerryM
10-16-2013, 08:16 AM
I have 2 30 br,s both have 334 necks, {no turn}
all I do is turn the high spots off the cases after fire forming them I have little trouble with the cases .
I do have a shorter case life but that's about it. Both are 16 twist and shoot very well.

SGJennings
10-16-2013, 08:45 AM
If you are turning the high spots off, it isn't a "no turn" neck. It's a "skim turn" or "cleanup" neck.

GerryM
10-16-2013, 08:52 PM
That's correct I could leave them the way they are, But I skim turn them.
The cases are usually off by 1/2 thousands .0005 that what I turn off. sometimes a few are a tad more in variation I turn those a tad more and keep them together in a separate group.
I've found groups are better this way. For general shooting it changes a tad more if you don't turn them. I shoot groups not score.