Neck sizing for F class 308 W... different results for Redding Bushing vs Lee Collet

Munkey1973

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OK so this is a "rough-in" experiment before I process my batch of Lapua Palma 308 neck-turned brass.

The pics below are for the same brass/batch. But they are not what I plan to use for competition. Rather they are some Federal, mediocre, bulk brass that are once fired in my bolt gun (we all should use "garbage brass" for the "rough-in" setup of our dies and trimmers etc setups ?.. at least I think so).

I know with confidence (using a quality ball-micrometer) that both pieces of brass is averaged at 0.015 neck thickness .

Additional info..
I am using a Forster Co Ax press.
All of my brass is annealed after every firing -right after stainless steel cleaning and before any resizing takes place
Both pieces had their shoulders bumped back 0.002 with a Redding Full Size Die.... Note: regardless of which neck sizing procedure I choose to adopt after this post, I plan on a 0.002 shoulder bump going forward.

The pictures below show sizing die "contact imprints" using Permatex Prussian Blue transfer compound.

The brass on the Left

Was neck sized with a Lee Collet Die.
Screwed all the way down until it just touches the co-ax plate (no cam-over).
I really like how the blue compound in shows uniform sizing (no significant high/low spots ...also the imprint runs the entire length of the case neck all the way down to the shoulder junction.
What I don't like in that the centre mandrel of the Collet die is 0.3045... that is really tight (IMO).
I have an expander die for my neck turning lathe setup that should correct this problem since it has a diameter of 0.3065.

The brass on the Right

Was sized with a Redding Neck Die... without the expander.
Screwed all the way down until it just touches the co-ax plate (no cam-over).And I left the usually amount of "wiggle room" for the bushing at the top of the die.
The bushing used was 0.337 .. which should be 0.001 neck tension ( 0.001 = .308 + (0.015 x 2) - 0.337 ) my math is right ??
What I do not like about this die is that it does not resize all the way down to neck-shoulder junction. This is evident with the big blue gap just before the junction.

The Question:

Should I even care that the Redding Neck Die is not resizing the entire neck of the brass ?
Does it matter that the Redding is not going all the way to the neck-shoulder junction ?

I don't mind using the Lee Collet Die (even if I have an additional step of expanding the brass) if it result in a better finished product.

Is there a third option ? … for example a better 308 Winchester resizing for the Forster Co-ax press ?

zV9F6Ix.jpg
 
The main reason so many reloaders use the Lee collet die is because it produces less neck runout than bushing dies. This normally is done after using a body die to full length resize the case body.

Below is a cutaway of a Redding bushing die and the area between the red lines is not sized. Some say the unsized and larger diameter neck area helps center the case neck in the neck of the chamber. Others say the unsized section at the neck shoulder junction helps prevent donuts from effecting seating and bullet grip.

O5m9mBL.jpg


You also asked about other dies and my preference would be a Forster full length benchrest and seating dies and that make very concentric cases.

Below Kevin Thomas of Team Lapua USA

Y3IiYL5.jpg
 
Is the big blue gap the result of the "wiggle room" left in the bushing die? I always shoot for .003" neck tension with my Redding bushing dies.
 
The main reason so many reloaders use the Lee collet die is because it produces less neck runout than bushing dies. This normally is done after using a body die to full length resize the case body.

Below is a cutaway of a Redding bushing die and the area between the red lines is not sized. Some say the unsized and larger diameter neck area helps center the case neck in the neck of the chamber. Others say the unsized section at the neck shoulder junction helps prevent donuts from effecting seating and bullet grip.

O5m9mBL.jpg


You also asked about other dies and my preference would be a Forster full length benchrest and seating dies and that make very concentric cases.

Below Kevin Thomas of Team Lapua USA

Y3IiYL5.jpg

Thanks. That diagram explains it all for the Redding die.
I used to use the Lee Collet die for 223 remington. Back then I didn't bump the shoulders. The rounds worked great for the first 3 to 4 reloads, the run out got out of hand as high as .010... couldn't even chamber some of them. .... Agreed..ALWAYS bump the shoulders at minimum. When I reloaded 223 I also turned the necks while using the collet... never had a problem with doughnuts.

Thanks for tip regarding Forster Dies (it might make sense that I should use Forster dies in my Forster press)... do you notice if the resize all the way down the neck?
 
Lee will make you a custom size mandrel.

Yes I saw on their website they offer that... might cost quite bit to get to Canada. I once broke the aluminum cap on my 223 rem collet. I looked into ordering a replacement from Lee... given the cost of a replacement, I just a whole new die (which is how I ended up with this 308 w collet die).
 
Is the big blue gap the result of the "wiggle room" left in the bushing die? I always shoot for .003" neck tension with my Redding bushing dies.

Now that I saw the picture above, the thick gap before the junction makes sense... I used a 0.338 bushing to give a 0.001 tension.... if I had to guess, if I ran .003 tension (all else the same), then gap might actually get thicker as there might be more resistance going into the bushing.
 
Have made a ton of 308 ammo for FTR and use a Lee collet neck die. Have not found neck tension to be overly high... you might want to try as is before going with any custom part.

I would also suggest outside neck turning thinner. If running Lapua, consider a comparison between 15 thou and thinner. It might help you.

Definitely bump the shoulder each firing.

Let me know if I can help with 308 goodies.

Thanks

Jerry
 
Now do you bump the shoulders back?

I use a Redding body die (does it bump the neck when I resize the body? Or does it simply resize the body?) and a Lee Collet neck die.
 
Now do you bump the shoulders back?

I use a Redding body die (does it bump the neck when I resize the body? Or does it simply resize the body?) and a Lee Collet neck die.

If it is definitely a body die, it does its best to size the body within limitations of springback. It will also set the shoulder back if set up to do so. It does not touch the neck size. The Lee Collet Neck Die does nothing to the shoulder. If you do not set the shoulder back with the body or full length sizing die, you will need a shoulder die like a Forster Shoulder Bump Neck Sizing Die. If you bought the complete Lee Die setup for your caliber, to simplify, I would just use the Lee full length die, set up to bump the shoulder about 1 to 2 thousandths during the sizing process. Use the neck collet die after that to get the neck sized nicely. If you plan on using a bushing neck die (with the bushing), the necks should be turned after shoulder bumping about the first three firings. It gets complicated. Keep it simple for now.
 
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The shoulder IS bumped back with the body die... or at least it can be.... and if it doesnt, maybe it is a shellholder issue?

if you don't bump the shoulder, very quickly, that brass is not going to chamber smoothly

Jerry
 
The shoulder IS bumped back with the body die... or at least it can be.... and if it doesnt, maybe it is a shellholder issue?

if you don't bump the shoulder, very quickly, that brass is not going to chamber smoothly

Jerry

Oops, sorry, yes, forgot I have mine set to not bump the shoulder as I use the Forster die next. Jerry is absolutely correct, the Redding body die will bump the shoulder if it is set up to do so.
 
If it is definitely a body die, it does its best to size the body within limitations of springback. It will also set the shoulder back if set up to do so. It does not touch the neck size. The Lee Collet Neck Die does nothing to the shoulder. If you do not set the shoulder back with the body or full length sizing die, you will need a shoulder die like a Forster Shoulder Bump Neck Sizing Die. If you bought the complete Lee Die setup for your caliber, to simplify, I would just use the Lee full length die, set up to bump the shoulder about 1 to 2 thousandths during the sizing process. Use the neck collet die after that to get the neck sized nicely. If you plan on using a bushing neck die (with the bushing), the necks should be turned after shoulder bumping about the first three firings. It gets complicated. Keep it simple for now.

As per my OP, I use a Redding FL die (without the bushing and expander) to bump the shoulders 0.002. I know the Lee Collet will not change shoulder/head space dimensions.

Your point regarding neck turning is interesting to me. Now, I turned the necks on my competition brass (308 Lapua Palma) before I fire formed them... only shaved about 0.0005 off the thickness … they are currently at very consistent .014. I have NOT touched the dials on my 21st Century Lathe since....

I've never heard of anyone re-turning brass for the first three firings.
This is a new perspective to me.
Is it because some of the brass flows from the neck-should junction into the bottom of the neck after its been turned?
(I have witnessed this previously with 223 Remington neck turning in the past).

When you re-turn your brass, do you cut deeper or keep the same depth ?

Please elaborate if you are still following this post. I'd like to learn more on this re-turning idea.
 
As per my OP, I use a Redding FL die (without the bushing and expander) to bump the shoulders 0.002. I know the Lee Collet will not change shoulder/head space dimensions.

Your point regarding neck turning is interesting to me. Now, I turned the necks on my competition brass (308 Lapua Palma) before I fire formed them... only shaved about 0.0005 off the thickness … they are currently at very consistent .014. I have NOT touched the dials on my 21st Century Lathe since....

I've never heard of anyone re-turning brass for the first three firings.
This is a new perspective to me.
Is it because some of the brass flows from the neck-should junction into the bottom of the neck after its been turned?
(I have witnessed this previously with 223 Remington neck turning in the past).

When you re-turn your brass, do you cut deeper or keep the same depth ?

Please elaborate if you are still following this post. I'd like to learn more on this re-turning idea.

I don't re-turn after the fireforming process, that is the only time I turn the necks. I don't turn them when they are new. New brass will never be that size ever again. Every lot of new brass is slightly different, even from the same manufacturer. First three firings I only neck size with the Lee Collet die. I find it takes at least two and usually three firings before the brass is fully fireformed. That is when they get the full treatment of body size, shoulder bump, trim to length, neck size with Lee collet die, expand for neck turning, neck turn with 21st Century Lathe. That is the only time I turn the necks. From this point on I use the Forster neck shoulder bump die and monitor length so that the brass can be trimmed as required. One of the stages in my Redding T7 press is the Redding Instant Indicator set up to check shoulder length. I usually only body size or shoulder bump or trim every second or sometimes third reload from this point on as necessary. I try to work it as little as possible. The brass stays together as a group and if one piece starts feeling 'tight' on loading into the rifle, they all get the same required treatment(s) before they get reloaded next time, whatever it turns out to be. Clear as mud right?
 
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