Oh my aching neck!

[TommyD11730]

So as I made mention in another thread im getting a big increase in neck runout. Im only seeing the jump from .001 (after full length sizing) to in some cases .010+ after sizing the necks via a collet and gauge pins.
So whats the best way to go about trimming the OD to get back to the more concentric neck before I set the neck tension?

 

[Wheres-Waldo]

Can you link to your other post? I think you're saying you FL size and its good, then putting it in a neck collet die and getting a ton of run-out?
Put the fireformed brass in the neck die FIRST, then size the body second.

1.) Are you asking the best way to turn out TEN THOUSANDTHS of neck wall inconsistency? I could almost guarantee you don't have more than a few thousandths of variation... if that much.

2.) You need to isolate where the run-out is coming from and fix the issue, not mask it by turning necks and creating more (and potentially dangerous) problems for yourself. When your OD run-out is 0.01", what is your ID neck run-out?

3.)If your ID run-out is zero and OD run-out is 0.01" (or measuring with a ball mic or over a mandrel and indicator), that is neck wall variation and you need to send that brass to either the trash can or Ripley's Believe it or Not.

 

[Bigfatcock]

Stop using the collet is what I’d recommend.

 

[TommyD11730]

The run out is measured on the OD of the case necks. Im using a sinclair gauge. Lapua brass 308.
There is little to no runout after I full length size the cases with a Forster die with the expander ball removed.
The runout is being created when I then expand my necks with a Porters die and gauge pins.
Its been suggested the irregular ID is being transferred to the OD when the gauge pin passes through the neck.
If I was to use say a K&M neck turner you need to run their pin to size the brass for the cutting tool. So Im wondering if that would just move my irregular dimension back inside.

 

[spife7980]

If I was to use say a K&M neck turner you need to run their pin to size the brass for the cutting tool. So Im wondering if that would just move my irregular dimension back inside.

When you turn necks to an even thickness you remove those irregularities.

well if you do it right that is.

 

[ShtrRdy]

I really doubt the Lapua brass has that much variation in neck thickness.

 

[Baron23]

I guess my question is what purpose are you reloading this ammo?

Do you intend to compete at BR, for example.

I’m not a reloading expert by any measure, others like @spife7980 are voices to listen to, but even my slightly OCD ass doesn’t worry about O.D. runout as my focus is on I.D. and resulting neck tension on the projectile.

On the other hand, I rather agree w an old friend of mine who, when asked by a mental health professional what my friend thought an obsession was relied; “eh, something to do?” Lol

 

[Cascade Hemi]

The run out is measured on the OD of the case necks. Im using a sinclair gauge. Lapua brass 308.
There is little to no runout after I full length size the cases with a Forster die with the expander ball removed.
The runout is being created when I then expand my necks with a Porters die and gauge pins.
Its been suggested the irregular ID is being transferred to the OD when the gauge pin passes through the neck.
If I was to use say a K&M neck turner you need to run their pin to size the brass for the cutting tool. So Im wondering if that would just move my irregular dimension back inside.

The previous discussion was .003 to .005 runout. I doubt very much you'd have .010" of neck thickness variation since the necks are .0155 thick at most. If the mandrel is causing excessive runout then stop using the mandrel. What is your ID when it comes out of the Forster die and what are you opening the ID back up to?

Have you tried using the Forster die with the expander ball in it? Mandrel neck sizing isn't the only functional option, Forster has custom ground expanders just for this purpose.

 

[TommyD11730]

I dont believe I have made mention of neck varaition thickness in either thread. Only the runout that occurs on the OD of the necks that occur after sizing via the pins. If my posts were misleading to that effect Im sorry.
Fact is I dont own a ball mic to measure thickness varaitions. (Well I didnt till I just ordered one now)
Granted varaitions in thickness Im sure goes hand in hand with runout (im gathering after the pins run through the neck).
I was not getting runout on the OD of the case as bad with the Forster die with the expander ball installed.

 

[TommyD11730]

but even my slightly OCD ass doesn’t worry about O.D. runout as my focus is on I.D. and resulting neck tension on the projectile.

Just a BR shooter, dont compete but I do tend to fall down reloading rabbit holes.
Guess this all started out when the new pins show up, I use them and my OD runout doubles. Now if somone said, "hey no worries its ID you should be concerned with. Forget OD " I might be good with that.

 

[TommyD11730]

Also im fighting "flyers". Still fighting them after the first time out sizing necks vs expander balls. My hope was the gauge pins would help with neck tension and maybe help with flyers too.

 

[Snuby642]

Ya runnout.

Looks like your Porters die and gauge pin does not float to find center. Also from reading instructions it can be set up crooked accidentally.

Not bashing Porters for any reason but Sinclair's mandrells have none of those problems.

I suggest getting the Sinclair mandrell set up. Cost is small and my groups closed a minimum of 1/8 of an inch in 308 and up to 1/4 inch in 223 and 6.5g .

I take existing expander balls in fls dies out and pollish them down with a drill and sand paper (wet /dry) to a mirror finish 0.004 under bullet diameter. That let's them run smoothly and works the brass less.

Then use the 0.002 under mandrell with cases dipped in grafite right before loading, smooth going.

Sorry, the tool your using is the cause. The pin is in there crooked.

 

[TommyD11730]

Ya runnout.

Looks like your Porters die and gauge pin does not float to find center. Also from reading instructions it can be set up crooked accidentally.

Not bashing Porters for any reason but Sinclair's mandrells have none of those problems.

I suggest getting the Sinclair mandrell set up. Cost is small and my groups closed a minimum of 1/8 of an inch in 308 and up to 1/4 inch in 223 and 6.5g .

I take existing expander balls in fls dies out and pollish them down with a drill and sand paper (wet /dry) to a mirror finish 0.004 under bullet diameter. That let's them run smoothly and works the brass less.

Then use the 0.002 under mandrell with cases dipped in grafite right before loading, smooth going.

Sorry, the tool your using is the cause. The pin is in there crooked.

You make an interesting poing RE being centered. I did remove the collet from the die multiple times to inspect the install. Ran a couple different pins to see if one pin might be buggered.
Also ran the die in a Hornady lock n load adapter. The Hornady adapter has an O ring and I had hoped it would help with centering.
Ill give Porters a call tommorow, they seem like a nice bunch of guys.

 

[Snuby642]

Well hopefully they can get you running properly. Any brand of mandrell / pin set up should improve your loads over standard fls.

The Sinclair product seems idiot proof and that's a good thing for me. If a product has a point that can be screwed up I'm sure to find and try it.

 

[TommyD11730]

Ok here is a update of sorts...
I took 2 pieces of brass with the worst neck runout. .010 or a tad higher. I ran both pieces through my Forster die. One with the expander ball, one without. Both cases returned to .001/.0015 runout.
The case without the expander balls ID of the neck is .296. The one with the ball .305.
Ok, so I run the .269 mouth case through the gauge pin (.307) and check runout. Its back at .010.
I then run the .305 neck through the .307 pin and the runout does NOT increase.
Couple of things come to mind, perhaps the O ring on the lock and load adapter is causing the problem. Or perhaps the nut is not tight enough and pin moves in the collet.
Not sure and like they say YMMV.

 

[Snuby642]

Pin moving crooked in the collet under pressure bending the neck?

I don't know how much torque the collet can stand. May be just a collet replacement will fix it.

I have seen collects get ruined on a lathe setup I might have ruined one way back myself I forget.

They are sort of delicate and figity as I see it, but we used them back then. (I also suck at operating lathes) so wtf would I know. Lol

 

[Cascade Hemi]

How does it shoot when you use the Forster die and expander ball only?

 

[TommyD11730]

How does it shoot when you use the Forster die and expander ball only?

Its about a 3/4 moa rifle. However its still good to send 1 flier on a 5 round group.
Could it be me? You betcha.

 

[Cascade Hemi]

Is the picture you posted representative of how the rifle normally shoots? What is baseline with known good ammo? I think you added complexity where you shouldn't have, you can load exceptional ammo on the most basic dies.

Instead of chasing mandrels you can manage neck diameter by turning your necks and/or having Forster ream your die. The two lots of 308Win Lapua brass I have sitting here is nominally .015" thick and varies +.001". If you turned it back to .0125 it would come out of your die .2985". Hone the die .003" and keep the .306" ball. Then throw away the mandrels. Once all that is done you'll have free time to figure out why you have flyers.

 

[TommyD11730]

Oh sure I finally get my gauge pins sorted and now you want me to chuck them.
Story of my life.
Maybe this winter Ill explore sending the die to Forster.

 

[Cascade Hemi]

Oh sure I finally get my gauge pins sorted and now you want me to chuck them.
Story of my life.
Maybe this winter Ill explore sending the die to Forster.

Or try a Mighty Armory die.

I know how you feel, I have a box full of every mandrel. I think they're one of those trends that will fade away. If you're controlling your processes correctly mandrels for sizing other than turning are unnecessary.

 

[TommyD11730]

The way I operate if I started neck turning it would end badly. Would start with a Hornady and end with a IDOD.
My credit card company LOVES me. My wife, not so much.

 

[B y r o n]

You have mentioned that maybe neck turning would solve your runout problem but it doesn't seem that you have measured the neck wall thickness at multiple locations and those measurements indicate that neck turning is necessary.

 

[Cascade Hemi]

The way I operate if I started neck turning it would end badly. Would start with a Hornady and end with a IDOD.
My credit card company LOVES me. My wife, not so much.

21st Century makes a turning lathe that is reasonably priced. Just like annealing, you don't have to spend a fortune if you don't want to.

 

[TommyD11730]

You have mentioned that maybe neck turning would solve your runout problem but it doesn't seem that you have measured the neck wall thickness at multiple locations and those measurements indicate that neck turning is necessary.

Your right, have a ball mic inbound.

 

[TommyD11730]

Thats a nice tool for sure. Probably something Ill look into. Wonder how the mandrals work to mount it on the tool. Meaning how large the neck has to be sized.

21st Century makes a turning lathe that is reasonably priced. Just like annealing, you don't have to spend a fortune if you don't want to

 

[spife7980]

Thats a nice tool for sure. Probably something Ill look into. Wonder how the mandrals work to mount it on the tool. Meaning how large the neck has to be sized.

You use the expander mandrel on press to size the case neck .001 below caliber and that gives you a snug but not too snug fit on the turning arbor which is .002 below caliber to support the actual cutting.

 

[TommyD11730]

I spoke with the good people at Porters Monday. Explained how if I try to resize the necks on a piece of brass that hasent seen the expander ball 1st the runout gets nutz. Honestly he had no answers for me. He did think the Forster die was working the brass a bit too much. He suggested contacting Forster and asking them if what Im seeing is typical in neck diameter.
Forster was very nice on the phone. Told me what Im seeing isnt uncommon on thick brass like Lapua. They suggested having the die turned some so it wouldnt work the brass so much.
Last thing I tried was the same experement, 2 pieces of brass. One sized with expander ball one without. However I removed the Hornady lock and load adapter to see if it might be the culprit. Nope.... same results.

 

[Cascade Hemi]

You can try an appropriate neck bushing die too. There's a lot of ways to skin this cat. How much do you want to spend?