When to turn

[heikki02003]

Just wondering when you turn necks. I have brand new .284win WW brass and I'm going to neck turn just to clean them up (approx 80%). Do you turn necks before fireforming or after? Why? I like to trim to length after fireforming because the brass undergoes some serious stress and stretch that first fireforming shot. But what about neck turning?
My thinking would be to turn them after. I'm thinking I will:
1. Fireform
2. FL size
3. Trim to length
4. Run them through an expander mandrel
5. Turn necks

But I could:
1. Run them through an expander mandrel
2. Turn necks
3. Fireform
4. FL size
5. Trim to length

Any comments or opinions?
Thanks

 

[Mikecr]

I use your second process.
Turn first

For many, this is normal, as unturned brass will not fit into their tight chambers.

 

[mike33]

Only turn necks if you have a tight neck chamber.
mike

 

[Dano1]

You didn't say if this was for a .284 Win or a Wildcat off of the .284

I only neck turn when necking down a caliber or more. For example If I'm making .243 Ackley brass using .308 Win Brass, I neck turn before Fire forming. If I'm using .243 Win, I do not. I happen to use .308 Lake City Match for my .243 Ai so neck turning is essential, but I only have to do it once.

I am also turning my necks for my 6.5-06 AI brass because I'm making it out of .270 Win Brass, just to clean it up. and uniform it. I'm not taking a full cut either, just enough.

None of my rifles have match chambers, so it's not terribly essential for my Standard caliber rifles.

Dan

 

[boomtube]

"Do you turn necks before fireforming or after? Why? "

Before. Otherwise you would need to fireform again to have a concentric neck.

You are doing right to only clean up 60-80% of the necks, doing more than absolutetly necessary just makes an already sloppy fit to the chamber worse.

It may be worthwhile to make a chamber cast and measure the actual maximum diameter you are working with. Just working off loading buok drawings is misleading, our chambers tend to be significantly larger than you might think.

 

[mike33]

"Do you turn necks before fireforming or after? Why? "

Before. Otherwise you would need to fireform again to have a concentric neck.

You are doing right to only clean up 60-80% of the necks, doing more than absolutetly necessary just makes an already sloppy fit to the chamber worse.

It may be worthwhile to make a chamber cast and measure the actual maximum diameter you are working with. Just working off loading buok drawings is misleading, our chambers tend to be significantly larger than you might think.

Good point, i always heard turning necks on a factory chamber is making a mess out of a mess. I used to turn necks when i shot a 6 ppc .262 neck. Thats when neck turning is needed, also i was shooting custom bullets. One thing on neck turning shooting over the counter bullets they are no where close to a custom bullet almost every loaded round is going to be different gaining nothing. When i was shooting matchs with ppc i think i had 12 pieces of brass and of course all was turned. That had to be the biggest PITA i had ever done, i couldn't image sitting down and doing 100 pieces for my deer rifle.
mike

 

[heikki02003]

Thank you very much for the replies. Sorry for not providing more info. boomtube, you really put my mind to rest, I will turn before, because then the fireforming shot will centre the case neck in the chamber. Also, I thought that now they have nice clean inside necks and will not interfere with going onto the turning mandrel.
I have been reloading for a long time; I have just never turned any necks. I have no experience turning necks. For this build I am going with a relative tight neck camber so that I can clean up my necks to provide more consistent neck tension when seating my bullets. I load many rounds by hand with an arbour press and Wilson dies and I'm finding too much variance in seating pressure. By the way, K&M make an arbour press with a pressure indicator. I am convinced that these variations are due to inner none concentric case necks because I do have case neck wall differences per case and I'm using Wilson bushing dies (without an expander button).
If you have none uniform case necks, and only size using a bushing die, you are inevitably inducing none circular case necks. The answer to this is to use an expander button. Out of personal preference I don't like expander buttons. So my answer to the problem is to build a tight neck (.003" clearance total) chambered rifle and turn the brass.
The rifle is built on a Surgeon SA repeater with Badger bottom metal, a 24" Kreiger 1:9.5" twist #5 contour SS barrel. The reamer is made by Dave Kiff at Pacific Tool and Gage, it's set up for .284Win WW brass with a .317 neck and .090 freebore. My WW brass with loaded rounds measure .314 to .316, I'm going to turn them all to .314, and plan on using a .312/.313 bushing.
Remember that turning necks removes material, making them thinner and more prone to splitting. As mentioned here, excessive neck clearance to chamber will make a "sloppy fit", and also weaken your case through excessive cold working of the brass through sizing. The .284 case is ideally suited to remove a thou or two as it's some pretty hefty stuff.

 

[boomtube]

"...K&M make an arbour press with a pressure indicator. I am convinced that these variations are due to inner none concentric case necks.."

Good thinking and you are quite right, so far as it goes. Unfortunately, other problems come into play too.

Consider that our brass is a mixture, not a compound. That means the alloy can - will - vary a little bit from one place to another in the same case!

Working the metal (necks) with firing and resizing also work hardens it, producing variations between supposedly identical cases!

Both of those factors makes it harder to qualify what is causing any neck seating tension/pressure variations we may measure with a scale.
-----------------------------------------------
ARRRRGGGH! This reloading stuff is much like a watermellon seed! It's awfully hard to get a firm grip on anything well enough that it can't squirt out!

 

[nheninge]

Saying you wouldn't neck turn brass just because your gun has a barrel with a factory neck is absolutely ridiculous. Some factory barrels shoot pretty darned good. You neck turn for uniform neck thickness (and therefore uniform neck tension on the bullet). This concept that taking a thousandth off will make a "sloppy neck chamber sloppier" is complete B.S. IMHO. A bullet has to leave the cartridge neck centered on the rifling and it will not do that if it is not released concentrically around the neck of the cartridge. Neck turning does not center the bullet on the rifling (good brass prep and a good barrel does). Neck turning DOES ensure all the brass surrounding the bullet behaves the same way as it expands regardless of tight neck, no turn neck, or factory neck.

 

[Mikecr]

Those are good points.

I would add for the fella using buttons(even though he hates them), that you can have the advantages of both approaches.
-Pulling a button improves seating straightness, but causes increased total runout, because the necks are often pulled off center.
-pushing a bushing allows straight necks, but causes runout due to ill seating because neck thickness variance is forced inside the neck -prior to seating.

The answer is to use a bushing for outside sizing, followed by mandrel for inside sizing.
With this, the necks are left straight as your chamber left them, and your bullets seat straight because any variance in thickness has been forced outside the necks.
Sinclair mandrels work perfect for this.

 

[nheninge]

I have noticed pulling/pushing a button essentially doubles whatever runout I have. 0.001 goes to 0.002 etc

 

[boomtube]

"This concept that taking a thousandth off will make a "sloppy neck chamber sloppier" is complete B.S. IMHO. A bullet has to leave the cartridge neck centered on the rifling and it will not do that if it is not released concentrically around the neck of the cartridge. Neck turning does not center the bullet on the rifling (good brass prep and a good barrel does). Neck turning DOES ensure all the brass surrounding the bullet behaves the same way as it expands regardless of tight neck, no turn neck, or factory neck"

Note that I did NOT suggest that all factory barrels shoot poorly nor that all factory chambers are "bad", only that factory (SAAMI) chambers are NOT snugly fitted to factory cartridges, and that's a fact.

Given that there is, indeed, already a good bit of excess space in factory chambers (that's why we must at least neck size our cases to retain a new bullet isn't it?) is it not clear that any increase in that already "sloppy fit" is deteremental to cartridge fit? And does it not follow that a sloppy fit is detremental to accuracy? If you think that's not so, why would many people choose to order tight neck chambers in their custom rifles?

No one here but you suggested that cutting a thou off a neck is supposed to be excessive in any way. ??? Kindly note that I DID agree that "cleaning up" maybe 75% of an uneven neck's circumference can be a good idea, so did others. Our point is that going beyond a reasonable amount in neck turning is NOT helpful to accuracy. And a LOT of competent people agree with that. IMHO.

Those were my stated points. What's yours?

 

[mike33]

Boomtube got a question for you. You seem a lot more knowigible on this issue than me. Here is my questions and experience with neck turning. Back in the 80's- mid 90's i shot benchrest with a 6ppc .262 neck. Of course i had to turn necks not an option. Just started loading than also, i asked guys of the time like Sinclair, masker, Hammond, top gunsmiths about neck turning on every day cart. with factory chamber. They all said the theory about making a mess out of a mess. So for one, with my experience of only turning about a dozen cases i did not enjoy the process and never turned for anything but my ppc. I still on any rifle case go the mile of de-burring and squaring primer pocket, etc. My ? is how much is turning really helping, does it show up on paper? Then when i was turning i was using custom bullets such as Euber, Hollister, and watson's ( dont even know if there around anymore ) These bullets were next thing to perfect and i always had my cases set to these bullets coming out to .261. So if your shooting ever day factory rifle with every day bullets and switching back and forth after turning necks arent you going to have a different reading. Yes, i have **** good factory rifles that shoot well also and not to proud to use them. If you was refering to me because i posted earlier i was only saying what i was told years ago. Maybe now there is a better tool than i had then but it was a pita for me years ago.
Mike

 

[nheninge]

My comments were more toward mike33 where "turning necks on a factory chamber is making a mess out of a mess" and "only turn necks if you have a tight neck chamber".

Taking a thousandth off brass in a factory neck should only improve accuracy if done properly. Why? I already stated my case for even bullet release. Aditionally, turning those necks reduces bullet seating neck tension for those using factory seating dies. Without neck turning I was getting 4-6+ thousandths neck tension (d/t thick uneven brass) which definetely makes a huge a difference. This could be avoided by using bushing dies of the appropriate diameter (if you have them and know how to use them). Feeling that bullet seat with a nice even 2 thousandths is sweet. My perception is that any slight increase in "sloppiness" is likely countered/overcome by even neck tension etc.

Tight neck chambers can also have their problems with accuracy/fliers without enough clearance (adding to my thoughts on even neck release), but if brass is prepped properly, they will beat the pants off a no turn or factory neck. Poor bullet release in either case (uneven release/too tight a neck) would be like trying to run through an open door with someone grabbing your left arm as you went through!

I never suggested cutting off a thou is excessive??? Taking a thou off is perfect. Sorry if you misunderstood. Somebody who takes the time to take thou off probably just cares more about the brass he is producing and will ultimately get better results.