Sizing procedure question

[David247]

I am reloading 6.5 Creedmoor with Lupua brass, using a Reading S type full length die with the bushing but expander removed, (necks are not turned), and follow it with a Sinclair mandrel expander.

I have been reloading for years but I took a reloading class by the the guy who built my gun and he said you don't need to use the mandrel expander every time you reload. Only on new brass that get a little beat up in shipping or if you don't catch your brass when they are ejected and they need to be uniformed.

I am trying to get my standard deviation in the single digits. They are running in the teens now.

Do you guys use an expander each time?

FYI, this will be the third reloading, they were all annealed using an Amp annealer, I use a Wilson chamber type seating die and K&M arbor, 40 grains H4350 using an FX-120i, 130 Berger hybrids, and I'm using a LabRadar Chronograph. I am trying to use the best equipment that I can afford (or sometimes not) to produce as precise rounds as possible. In addition to the question above, If you have other suggestions, let me know.

Sorry for the question turning into a book!!! Thanks

 

[spclark]

If you’re not using the expander ball that came with your Redding die, you need to use your expander mandrel every time, unless you’re using a bushing of way too large an ID.

Too, you may be overworking your brass something fierce if your bushing ID’s too small.

One tip is not to resize more than maybe 0.10” of the neck itself, then only run the mandrel in enough to ensure the portion sized has the desired ID, which may not put the expander in much at all.

I use bushing dies (Redding and Whidden) with appropriate bushings then expander mandrels every time. And I anneal... every reloading.

Don’t get hung up on SD alone. There’s more to reloading for accuracy than SD’s.

 

[HTSmith]

So I'll qualify by saying I've been reloading for 30 years, but only been in this precision world for a couple of years. I'll share a couple of experiences that may be helpful:
1. The amount of neck tension is important, and sometimes more is better. Your mandrel could be the "wrong" diameter.
2. The bullets themselves can make a difference. I recently developed a load for a new (to me) rifle using bullet "x" that had given me great results in two other rifles of the same caliber. I developed an accurate load, but the ES/SD's were nearly double my other rifles. On a lark, I tried bullet "y" that I'd set aside years ago as being inferior. The groups tightened up ever so slightly, but the ES/SD was cut in half. So the lesson for me was feed it what it wants, not what you want it to have.

BTW I am jealous over your "stuff"

 

[dstoenner]

I have to disagree with your statement you are not turning necks. If you want precision and consistency you need to turn necks. Once you turn them an see all of the highs and lows on the necks you will see what you are missing. And once you have turned your necks then you can reliably set your nevk tension with the sizing bushing and never have to do the mandrill again

David

 

[JFrank]

I have to disagree with your statement you are not turning necks. If you want precision and consistency you need to turn necks. Once you turn them an see all of the highs and lows on the necks you will see what you are missing. And once you have turned your necks then you can reliably set your nevk tension with the sizing bushing and never have to do the mandrill again

David

David
Isn't the need for neck turning determined by the reamer ?
I know a lot of shooters using no turn necks producing excellent ammunition.
Jim

 

[DirtySteve]

Did you deburr your flash holes? Consistent ignition will help get your SD down.

 

[David247]

If you’re not using the expander ball that came with your Redding die, you need to use your expander mandrel every time, unless you’re using a bushing of way too large an ID.

Too, you may be overworking your brass something fierce if your bushing ID’s too small.

One tip is not to resize more than maybe 0.10” of the neck itself, then only run the mandrel in enough to ensure the portion sized has the desired ID, which may not put the expander in much at all.

I use bushing dies (Redding and Whidden) with appropriate bushings then expander mandrels every time. And I anneal... every reloading.

Don’t get hung up on SD alone. There’s more to reloading for accuracy than SD’s.

Thanks for the info but now I have more questions?

1- Tom Sarver, Thunder Valley Precision built my rifle and got the reloading supplies that I needed. He is a top notch smith and I doubt he gave me the wrong bushing but it's new to me so how can I tell?

2- How do you size only .10 of the neck when it is a FL die?

3- How in the heck do you only allow .10 of the mandrel to go in? I know how to adjust it but how do you know that is set to only go in .10?

 

[dcali]

I don't even own an expander mandrel, and never use one. I also never use the expander ball. I do turn necks and use small primer brass. That's it. SDs are typically in the high single digits, and occasionally in the low double digits - 7-12 fps. (This is a .308)

Two things I would try: get some small primer brass (you should use this anyhow), and maybe try turning the necks. A different powder may help.

But a bigger question is why do you want smaller SDs? are you getting vertical at long range?

 

[David247]

Did you deburr your flash holes? Consistent ignition will help get your SD down.

No, I read somewhere here lately that you are better off to leave the flash holes as is on Lapua brass. Like most anything else on the net, don't know if that was good advice or not. I do know though that during the reloading session I mentioned above, that did not come up.

 

[David247]

I have to disagree with your statement you are not turning necks. If you want precision and consistency you need to turn necks. Once you turn them an see all of the highs and lows on the necks you will see what you are missing. And once you have turned your necks then you can reliably set your nevk tension with the sizing bushing and never have to do the mandrill again

David

David,

I am not shooting Bench Rest competition but I would like to try turning them anyway. I am only trying to hit 1' square steels way the hell out there. I shoot at Thunder Valley Precision in east-central Ohio and he has a course called head hunter which has steel targets with spring loaded heads that collapse and come back up when hit. They are actual head sized targets out to 600 yards or so. It is very hilly with lots of changing winds. Fun as all get-out but it is tough! He also has targets out to a mile and he was saying that to smack them, your SD's better be single digit.

I have never turned necks before but would like to try and see the difference it makes. How do I know how much to take off and what size bushing I would need after turning them? I will search to see if there is a good article or other posts also.

Thanks,

David also!

 

[Mozella]

David
Isn't the need for neck turning determined by the reamer ?
....... snip..........

Yes and no. Some reamers cut a chamber which is smaller than normal in the neck area and if that is the situation, then you MUST turn the necks or else you can't chamber the round or perhaps the clearance is too small to be safe. That's one obvious reason to turn necks.

If the reamer used on your action allows you chamber brass with un-turned necks, then you don't have to get involved in neck turning.

However, if you have a good neck turning lathe, you can easily see that taking a skim cut on a neck will reveal that neck thickness is not perfect all the way around. In other words, some parts of the neck are thicker than others. Neck turning will take off the high (thick) spots. And, don't be surprised if the next case you turn is more uniform. So not only is any individual neck possibly uneven, it is unlikely to match the next case in line.

If you're like me, you believe that uniformity and consistency are likely to improve your scores. So many of us turn our necks to make them as consistent and uniform as possible even though it may not be absolutely necessary when it comes to fitting the brass into the chamber.

By the way, if you decide to get into neck turning, do yourself a favor and get a good rig like the 21st Century lathe and cutter head. It's a bit expensive, but well worth the money and makes neck turning almost a joy. Cheaper options make turning an unpleasant task.

 

[DirtySteve]

No, I read somewhere here lately that you are better off to leave the flash holes as is on Lapua brass. Like most anything else on the net, don't know if that was good advice or not. I do know though that during the reloading session I mentioned above, that did not come up.

Lapua now punch the flash holes. They no longer drills them. They do a very good job of punching them but there still is a burr. Your question was about sizing and wanting to get down your SD. Brian Litz has.stated in his books that informing the flash holes helps bring them down.

 

[mikecr]

How do you size only .10 of the neck when it is a FL die?

The 'Redding type S FL bushing die' is not a FL die. It's a body-bushing die.
What's the difference? The bushing does not size the FL of the neck. With the bushing die you have adjustment of neck sizing LENGTH as well as neck sizing DIAMETER.

How in the heck do you only allow .10 of the mandrel to go in? I know how to adjust it but how do you know that is set to only go in .10?

Mandrel expansion length usually makes no difference, but it could.
Your cases, including necks, are never straighter than pulled from a smoking chamber. It's die sizing that messes everything up from there. A neck bushing partial length sizes necks, leaving the lower portion of necks untouched and therefore still straight. It's prudent to set a neck sizing length that is no more than 3/4 of your necks. This might be .10" or more or less, depending on the cartridge. It doesn't have to be an exact value to begin but ~.10" of neck sizing length is plenty enough area to grip seated bullet bearing.
If you only size let's say 1/2 the neck, then running an expander mandrel all the way through necks will not matter, as that expander is only working on the portion you had sized. That is, unless you have a lot of donut built up near the neck-shoulder junction. In this case, you don't want to size donut up or down, and you shouldn't seat bullet bearing into this area. It's just bad in every respect. Since you don't want to upsize donuts, you don't want to run your expander through them. And if you're smart, you will never downsize donut area (FL size necks). What if you have to seat bullet bearing all the way into donut area? Well, bullets make terrible expanders (they're too soft). You don't want to up size necks with seating of bullets. This is what neck pre-expansion is all about. So in this case, it's better to run an expander mandrel right through donut area (FL expansion), and have enough neck clearance to accept donut area as pushed outward (away from seating bullets).

People use expander mandrels(instead of die buttons) as a separate process because this doesn't pull necks out of straight.
And you could of course skip this, pick the right bushing to provide 1thou interference fit after spring back, but you're then missing an advantage of neck pre-expansion: driving thickness variance outward, away from seated bullet bearing, for straighter loaded ammo.
Pre-expansion is not needed with turned necks, and not producing and bringing donuts into play, and where you're using a correct size bushing.

 

[dcali]

The 'Redding type S FL bushing die' is not a FL die. It's a body-bushing die.
What's the difference? The bushing does not size the FL of the neck. With the bushing die you have adjustment of neck sizing LENGTH as well as neck sizing DIAMETER.

This is not how my Redding FL type S dies work. Mine sizes the whole neck. You would have to put a spacer in under the bushing to accomplish any length adjustment on neck sizing, which might work, I suppose, but I'd want to cut those spacers pretty close to the unsized neck dimension. Maybe someone has done this.

 

[Uncle Ed]

Redding now recommends a bushing .002 smaller than a loaded round due to brass spring back after sizing.

Redding also recommends if the necks are not turned to use a bushing .004 smaller than a loaded round and then use the dies expander. Meaning the expander is used to make the inside of the case neck a uniform diameter.

Tech Line & Tips (FAQs)
Bushing Selection
https://www.redding-reloading.com/tech-line-a-tips-faqs/140-bushing-selection

The above methods of determining bushing size require that the cases being sized have a fairly uniform neck wall thickness or have been neck turned. If the neck wall thickness varies more than 0.002", it may be necessary to use a bushing a couple of thousandths smaller than your calculations indicate, and then use a size button in the die to determine the final inside neck diameter.

https://www.redding-reloading.com/tech-line-a-tips-faqs/132-faqs1

Question: What Bushing do I need for my Type "S" Die?

Answer: There are two methods for choosing the correct bushing. They are as follows:

1) Measure the neck diameter of a LOADED round or a "dummy" round that you've produced with the brass & bullets you plan to use. Now, simply subtract .002 from the diameter you measure to select the correct bushing size.

a. The use of a Micrometer is advised for these measurements but a Dial Caliper may be used if a Micrometer is not available.

b. Measuring a sample (several) loaded rounds and using the average is advisable.

Example:

My loaded rounds measure .300 at the neck.

.300 - .002 = .298

Thus, a .298 Bushing would be appropriate.

2) If loaded/dummy rounds are not available, mathematically create the diameter of a loaded round using the brass & bullets you plan to use.

a. Use a Ball or Tube Micrometer (micrometer designed to measure curved surfaces) to measure the thickness of your case necks. Note that a Redding Case Neck Gauge (PN 26400) may also be used to measure case neck thickness.

b. Multiply this number by 2 to account for each side of our theoretical "loaded round."

c. Add a bullet diameter

d. Now subtract .002 to select the appropriate bushing size.

Example: My case necks are .014 thick.

.014 x 2 = .028

My bullet Diameter is .284

.028 + .284 = .312

Now, subtract .002 to select the appropriate bushing size.

.312 - .002 = .310

 

[smoooth]

"This is not how my Redding FL type S dies work. Mine sizes the whole neck. You would have to put a spacer in under the bushing to accomplish any length adjustment on neck sizing, which might work, I suppose, but I'd want to cut those spacers pretty close to the unsized neck dimension. Maybe someone has done this. "


Loosening the plug screw that holds the expander rod AND the bushing will provide plenty of adjustment for said bushing to move vertically thus providing the desired amount of neck sizing. No spacers needed....ever.

 

[Uncle Ed]

This is not how my Redding FL type S dies work. Mine sizes the whole neck. You would have to put a spacer in under the bushing to accomplish any length adjustment on neck sizing, which might work, I suppose, but I'd want to cut those spacers pretty close to the unsized neck dimension. Maybe someone has done this.

Redding bushings are slightly tapered and may not size the neck the same diameter at the neck shoulder junction.

Below the inside bottom of the bushing is tapered, there have other postings here where member brought this up. The good point of this is any donut will not be pushed to the inside of the neck with the tapered end.

 

[mikecr]

The top plug adjusts for neck sizing length. This is how you adjust neck tension (not with bushing size).
And I highly doubt this die can FL size necks. Close, but not all the way.

 

[spclark]

.002" undersized may be correct, or .003" or .001" depending on what you find your rifle likes.

Same with 3/4 of the forward end of the necks being sized, or 1/2, or 1/4, or whatever fraction you find is enough to hold the bullet adequately for traveling to the range as well as maintenance of the particular seating depth you find your rifle likes.

As to how to adjust bushing for this? Easiest is simply not to run the bushing stop plug in too far... stop plug prevents bushing from moving up when a case neck is inserted, but that plug doesn't have to be run it as far as it can be to keep a bushing in firm contact with the base of the die's bushing bore.

I've added a larger ID bushing under the one I've selected to size the case neck; that larger ID bushing becomes a spacer. This isn't a common procedure though, but came in handy when I was making 6XC brass out of Lapua's 308 Palma brass.

Same principle applies to neck mandrels. You want to use enough of the shape of the mandrel to ensure your necks are sized to the desired ID. This doesn't necessarily mean you have to set your mandrel die up to push the entire length of the mandrel through the portion of your case necks the bushing has sized. Sometimes it's enough just to use the portion - ogive if you will - before the mandrel reaches it's full, parallel-sided diameter. Back off on the depth the mandrel die is screwed into your press, and pay close attention to how far the mandrel retaining plug is screwed into the die at the top end to do this.

Sometimes it's enough just to use that ogive portion of your mandrel to very slightly 'bell' the neck mouths enough to ease seating bullets and no more. This leaves the remaining portion of the bushing-sized necks to grip the bullets' bearing surface, while the unsized portion behind remains as straight as Mikecr alludes it can be.

These reloading tools we use have adjustment features that are designed in for reasons that frequently remain elusive until they either dawn upon us one day when we're struggling to achieve greater accuracy of our reloads, or are revealed to us by others - perhaps here - who've stumbled upon them thru trial and error.

 

[dcali]

Does that work with so much travel? I've admittedly never tried. But yes, my .308 dies size all the way to the shoulder/neck junction.