neck turn or FL bushing size

I’m just wondering if necks turned will suffer going through a FL die and expand mandreled.

No , remember you're just making the neck walls the same thickness all the way around . Meaning there is always one section of the neck ( thinnest before turning ) that get turned down VERY little to not at all . You're not turning the whole neck several thousandths , only shaving off portions of the thicker sections . If it were to actually hurt the brass that would seem to suggest thinner walled case necks are bad and you would never see thinner walled case necks on brass and yet manufactures case necks thickness vary considerably from brand to brand .
 
Back in the 1960's when good match bullets were available in all calibers, good marksmen learned that using anything to expand the case neck after resizing it down results in accuracy loss.
 
I turn .001 and a half.

I watched a YouTube video saying about a guy named glen zediker saying expandermanderls are the way to go for neck tension/concentricity
 
Unfortunately, Glen Zediker passed away last year. He was a long-time competitor and a prolific author. I've got some of his books and liked them and his articles.

From an engineering standpoint, the conical shape of the shoulder of a bottleneck case should be more rigid in compression (pushing the expander in) than it is when pulling the expander out, and I've confirmed this by measurement to be true, as Zediker said. However, the ultimate way of avoiding any deformation is to do neither type of expansion, but rather resize the neck in the right bushing or in a honed die to make expansion unnecessary. Hummer70 told me he has something like 158 resizing dies in 308 Winchester. This is the result of seeking perfect matches to chambers cut by different reamers. So it can add up.

The other way to go about avoiding an expander is to use the Lee Collet Die for the neck and the Redding body die for the rest of the case. This old video shows how the Collet Die produces essentially no neck runout.
 
I have a Lee .30-06 neck collet die. I'll give it a try and see how much neck tension I have after bullet seating. IDK if I will get .001 neck tension like I have now, though. We'll see.

As far as deformation with either way of expanding, my accuracy results are stellar with expanding manderling as we speak.

Hummer70 had to have 158 dies honed before he had the right neck diameter to match his chamber neck?

Redding body die and Lee collet, sounds interesting.. hmmm. yeah I like it.
I just need a body die. Consistent results in sizing, verses FL die and expander aye? And Neck shoulder body being true with each other ? So the body die does just that sizes the body and sets the shoulder back.... ?

After all said and done with FL, Expander Mandrel, and even Forster BR seater, I still have 4- .006 bullet runout. Ya got me wanting this body die, now.

I bought expanders and Forester BR seaters and one Wilson inline seater,(.270). I sent the Wilson back for repairs, and they talked me into a custom seater with a fire formed case. Long story short....004- .006 bullet runout ..004 most times with the Forster (06'). Grouping at 1/2 MOA no neck turn, almost one hole neck turned.

You are the first who mentioned a Lee neck collet and a body die and the video to show virtually no run out. The guy on the vid said his fingers were causing the variation on the indicator.

Just after I posted this, I remembered the neck runout with my expander mandrels. -.001, after bullet seating the same, -.001
 
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...And if you don't get tight enough necks from the Lee, you can chuck the mandrel in a drill, and with a loop of wet/dry sandpaper, reduce its diameter until you get what you want. I also lapped the ones I have to make the collet close more smoothly. Lee fit and finish can be a bit rough, but the concept is great.

Hummer70's die collection is from having 158 different chambers, with each die honed to match one of them. He's got a special match reamer pattern he uses that was designed by a ballistic whiz he knew at Aberdeen PG, IIRC.
 
milboltnut, I have worked around those issues. I use a deprimeing die to remove the primer and have removed my expanders from all my FL dies. I run the case through the die twice, rotating the case 90 degrees. I check every case for runout. I then use mandrels to expand, going through the mandrel twice, same procedure. If a case is out more than .001 I start over. The bullet seating is my problem and I just start a bullet, take it out and use the Hornady alinement tool to straighten it as much as possible before setting to OL. I can generally get the bullet runout below .003 on a RCBS gauge.
 
Yes if you want a body die and at any time plan to use a bushing die . Buy a FL bushing die and use it with out the bushing . This will only size the body and shoulder if applicable .
 
Ok, update

I used my Lee collet die on a fired neck turned .30-06 case. As I said, the decapping mandrel is .304. I ran the die until the collet completely closed. The OD of the sized neck is .328. After seating the bullet the OD of the neck is .329. Same results as with the expander mandrel, but less work. In my mind I thought the Lee mandrel had to be bigger. Guess not. I thought I retired this die for good, and payed it no mind and never seen an increase in accuracy in the past. I also ran the neck over my .306 neck turning pilot and it slides with ease.

I had two exceptional group, I wouldn't say were completely accomplished by neck turning and expander mandrel alone, bedding my M70 was another contribution. I was told by a guy that repeatability isn't common, and that I would might be disappointed. Thinking maybe he's right now.

Will body die/collet die verses FL die/expanding mandrel make that much of a difference?
avoiding any deformation
and was trying to figure out how to describe the "true" alignment of a case after sizing...
the collet die.. the neck is formed to the mandrel which tends to form the neck straight and along the axis of the cartridge.
I know this but I figured I'd post for guys who don't post but just read.
If one side of he neck is slightly more "dense" than the other, the neck is sized off center. The Collet Die is not prone to this.

One last thing...... I mentioned before the runout on a turned neck, .0015 to .001.. IIRC. Deformation is there.

I tossed my casemaster. Didn't like it much, shoulda kept it a little longer LOL It was a free bee.....LOL I want a 21st Century

But I trust the video you posted Uncle nick it's good enough for me.

the concept is great.
I agree.... collet/mandrel, equal amount of force inside and out, verses expander mandrel with no outside reinforcement.

Body die needed. Thanks !
 
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The Redding FL bushing also come with

A decapping pin retainer is also supplied with most Type S - Bushing Dies except 17 and 20 Cal. This enables neck sizing without the use of the size button for those who sort and/or turn case necks for uniformity.

You buy bushing instead of mandrels.
 
I like the idea of FL bushing die used as a body die. Leave bushing out and it's a body die, and later if I decide to use bushings, I can.

How true is this?
The Redding bushing dies transfer bad runout to the inside diameter of the case neck, while the Lee Collet Die places the lack of concentricity to the outside and leaves the inside diameter a mirror image of the mandrel, which has no runout.

A tube mic would pick up deformations wouldn't it? Even with necks turned and having say .012 neck thickness all the way around?
 
If you don't have a special neck wall runout measuring tool, the tubing mic will work to learn the neck wall unevenness. I find I get much better results having the tubing mic in a micrometer stand. Harbor Freight used to have a really cheap one that worked fine, but they seem to have dropped it. A small padded vice will work, too.

The Redding bushing type resizing die will give you both options, but the Redding body die alone is half the price. Currently in stock and on sale at Midway.
 
I think it was explained, This enables neck sizing without the use of the size button for those who sort and/or turn case necks for uniformity.
 
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