Sizing Die Faceoff

[nick338]

Brainstorming about which sizing die/process I want to pursue for a 300 Norma. Since SAC isn't making a sizing die for it yet, I have narrowed my choices to a custom honed Forster FL sizing die, removing the decapper and using a mandrel to size the neck, or Bullet Central makes a bushing die with the option of full neck sizing or partial neck sizing.

Concentricity is important or I'll lose sleep at night. But more important is shooting the difference and determining if there is any between the 2 setups. Is the partial neck sizing keeping the brass closer to my chamber dimension thus leading to better accuracy?

Lemme know.

 

[Winny94]

this is just another iteration of "which way is best" that inevitably devolves into a pissing match between guys who both have more than sufficient processes that work for them.
Really the best advice is find a shooter you like and do what they do, there isnt a single right answer. Personally, I think Erik Cortina makes a strong case for simply FL sizing, and I like Forster dies w/o the hassle and additional part of the bushing so im partial to that option. Just pick and be consistent. All will make loads that we probably can't out shoot.

 

[Dogtown]

FWIW, with my precision cartridges I've refined things to the point where I basically use a Redding Body Die for shoulder bump, and a Redding S Bushing Neck Die for sizing the neck, and a 21st Century mandrel for neck tension. Yes, breaking it out into separate operations is more time consuming, but I find it's a more controllable solution (especially when I need to tweak necks and don't want to FL size again).

 

[Maurygold]

I've owned most dies. I'm a big fan of Whidden. I only used a expander die when shooting f class on large caliber I leave the expander in the sizing die

 

[nick338]

this is just another iteration of "which way is best" that inevitably devolves into a pissing match between guys who both have more than sufficient processes that work for them.
Really the best advice is find a shooter you like and do what they do, there isnt a single right answer. Personally, I think Erik Cortina makes a strong case for simply FL sizing, and I like Forster dies w/o the hassle and additional part of the bushing so im partial to that option. Just pick and be consistent. All will make loads that we probably can't out shoot.

I just hate leaving anything on the table, especially when it comes to shooting any kind of distance.

 

[Maurygold]

I just hate leaving anything on the table, especially when it comes to shooting any kind of distance.

you aren't. full size will get you there. If you don't believe us take a shotmaker and go set it up at 600 yards and see which shoots better if there's any difference.

 

[Choid]

The Bullet Central dies are very, very nice.

 

[nick338]

FWIW, with my precision cartridges I've refined things to the point where I basically use a Redding Body Die for shoulder bump, and a Redding S Bushing Neck Die for sizing the neck, and a 21st Century mandrel for neck tension. Yes, breaking it out into separate operations is more time consuming, but I find it's a more controllable solution (especially when I need to tweak necks and don't want to FL size again).

You can really give yourself a headache trying to make a decision, especially if you ask 10 different people and they all have a different answer and their way is always the best.

Or a new product comes out that for some reason the shooting community shouldn't be without because it does a better job than anything that preceded it.

I'm not a volume loader so extra steps don't really bother me. I would have to try every possible combination to quantify the differences so I'm hoping the law of averages with information here guides me in the right direction.

 

[MarshallDodge]

Brainstorming about which sizing die/process I want to pursue for a 300 Norma. Since SAC isn't making a sizing die for it yet, I have narrowed my choices to a custom honed Forster FL sizing die, removing the decapper and using a mandrel to size the neck, or Bullet Central makes a bushing die with the option of full neck sizing or partial neck sizing.

Concentricity is important or I'll lose sleep at night. But more important is shooting the difference and determining if there is any between the 2 setups. Is the partial neck sizing keeping the brass closer to my chamber dimension thus leading to better accuracy?

Lemme know.

SAC isn't the only answer. I've been very happy with Whidden and Wilson. Redding makes good stuff as well. I've just started playing with mandrels for 223 and that seems to be where the magic is.

 

[CK1.0]

Like has been said (before this devolves into the usual Hide pissing contest), in the end, there's pronbaly more than one right way.

That said, I'm a huge believer in using a mandral after FL sizing and ditching any form of expander-ball. And, up until recently, as far as sizing before the mandral I used to lean more towards the opinion that, before the mandral, a custom-honed FL die was "best", with a bushing die being "better", and a regular old neck-squashing FL die being "good until you get one of the other two better/best options".

Lately though, I'm finding I'm gettting some of the best ammo I've ever made (group-wise, waterline-downrange-wise, and ES/SD-wise) by using the regular old neck-squashing FL die followed by the mandral. Though, I'm pretty sure the fact that I anneal every firing on an AMP is a big part of why this recipe is working so well, and I wouldn't recommend doing it this way if one didn't anneal every time too.

FWIW, I had been using a Wilson die with a TiNi Redding bushing, but lately it's been a Lee with its guts removed, think it was ~$18 lol.

 

[MarshallDodge]

.....
FWIW, I had been using a Wilson die with a TiNi Redding bushing, but lately it's been a Lee with its guts removed, think it was ~$18 lol.

Some of the best groups I have ever shot had ammo that was made on a Lee die.

 

[CK1.0]

Some of the best groups I have ever shot had ammo that was made on a Lee die.

I like Lee stuff, you'll get no anti-Lee snobbery from me, but honestly it probably could be anybody's regular FL sizing die...

I had tried it (purposely using the neck-squashing normal FL die on a freashly annealed case followed by a mandrel) once before, but I didn't like how they felt when seating bullets. It felt like the neck tension was way stronger and a lot more inconsistent than I was used to. I loaded 100 like that and then shot the first 50. I can't even remember if the conditions were good or bad, but they seemed pretty meh, and I crono'd 5 or so and the numbers looked shitty, so I went back to my bushing die setup that didn't squash the necks nearly as much.

At the time I had a bunch of my usual rounds already loaded, so I didn't shoot the second 50 of the batch for quite a while, but when I finally did shoot them, not sure if I was just having a good day or what, but I remember thinking "damn, these aren't nearly as bad as I thought" and I was stacking round after round in the middle of a 1moa plate at 750yards, prone/tank trap/PRS jerk off prop... no problem.

Even though I went back to the bushing die, since then I've evolved to where besides all the usual stuff (mandrel, anneal, chamfer), I now also lube the insides of the case necks real quick before seating bullets with some q-tips with a few sprays of lanolin/IPA case lube on them, nothing crazy, but it's easier and less messy than graphite IMHO and makes seating bullets an experience approaching nirvana lol.

Anyways, I decided to give the anneal>regular FL die>mandral thing another try again, this time with the q-tip/neck-lube before bullet seating, and so far, through ~500rds, I'm digging it. Consistent at the handle and downrange. Something is different though, in a good way I think, and I was making single-digit SD good shit before...

(YMMV/caveat emptor)

 

[Jefe's Dope]

I'm still pretty much a rookie in reloading but I had the Whidden 6.5 CM FL no bushing sizer and was very happy with the results. I'd buy again.

I'm running "The" Sizing Die from SAC currently for my 6GT. Just getting started, so no real feedback. Alan in CS is fooking awesome though. Got me all set up with a mandrel/decapping pin they don't even sell yet.

 

[Steel head]

The whidden die I have seems pretty good.
If you go BC bushing do a full neck resize, bigger magnums seem to like a good grip on the bullet.

 

[nick338]

Using new Lapua cases to load develop, all I did was use a little Hornady One Shot on the inside of the neck, a .306 mandrel, slight chamfer and loaded up. Seemed like with .002 neck tension most loads were averaging 10-12 ES.

 

[Clark]

Concentricity is important or I'll lose sleep at night. But more important is shooting the difference and determining if there is any between the 2 setups. Is the partial neck sizing keeping the brass closer to my chamber dimension thus leading to better accuracy?

Lemme know.

Ammo concentricity has a mathematical relationship with group size as published NRA A.A. Abatto.
But ammo is inserted in the chamber with random rotational orientation.
Cut chambers with eccentricity are fixed orientation.
While we shoot ammo that is 0.0050" concentric and that matters, we chamber while dialing in to 0.0001" and that does not matter.
The reason we are backwards is ammo is recurring effort and chambering is a one time effort.
We have a wrong way caveman heritage industry to make cheap arrows and expensive bows.... because making arrows is so much work.

*MATHEMATICAL SOLUTION

A laterally displaced center of
gravity moves through the rifle bore
in a helical (screw) path. The pitch
of this helix is the pitch of rifling,
and its radius is the lateral displace-
ment of the center of gravity. On
leaving the muzzle, the center of
gravity continues in the direction it
had at that point. For example, if it
leaves at top of the bore and rifling
is to the right, the departure will be
to the right. The bullet travels ap-
proximately 2l.5" in a 24" barrel,
making 2.15 turns in the 10" twist
of rifling. The number of turns
shows the orientation on emergence
compared with that in the chamber
before firing. The angle of emer-
gence is that angle whose tangent is
2 pi times the lateral displacement
divided by the rifling pitch. For
.004" point displacement and I0"
rifling pitch, the tangent is 1/8(2·pi)
(.004)/l0 and the corresponding
angle is 1.1 minutes.
The displacement on target from
this cause is proportional to the
range and can be obtained without
noting the angle. For example, ,004"
point displacement gives in l0"
rifling pitch, so far as this mecha-
nism goes, a target displacement at
100 yds. (3600") indicated by the
proportion .00l· pi /10=X/3600, from
which x =1.1".

 

[smoothy8500]

I just hate leaving anything on the table

The only thing you're going to leave on the table is more cash....

 

[Seymour Fish]

Ammo concentricity has a mathematical relationship with group size as published NRA A.A. Abatto.
But ammo is inserted in the chamber with random rotational orientation.
Cut chambers with eccentricity are fixed orientation.
While we shoot ammo that is 0.0050" concentric and that matters, we chamber while dialing in to 0.0001" and that does not matter.
The reason we are backwards is ammo is recurring effort and chambering is a one time effort.
We have a wrong way caveman heritage industry to make cheap arrows and expensive bows.... because making arrows is so much work.

*MATHEMATICAL SOLUTION

A laterally displaced center of
gravity moves through the rifle bore
in a helical (screw) path. The pitch
of this helix is the pitch of rifling,
and its radius is the lateral displace-
ment of the center of gravity. On
leaving the muzzle, the center of
gravity continues in the direction it
had at that point. For example, if it
leaves at top of the bore and rifling
is to the right, the departure will be
to the right. The bullet travels ap-
proximately 2l.5" in a 24" barrel,
making 2.15 turns in the 10" twist
of rifling. The number of turns
shows the orientation on emergence
compared with that in the chamber
before firing. The angle of emer-
gence is that angle whose tangent is
2 pi times the lateral displacement
divided by the rifling pitch. For
.004" point displacement and I0"
rifling pitch, the tangent is 1/8(2·pi)
(.004)/l0 and the corresponding
angle is 1.1 minutes.
The displacement on target from
this cause is proportional to the
range and can be obtained without
noting the angle. For example, ,004"
point displacement gives in l0"
rifling pitch, so far as this mecha-
nism goes, a target displacement at
100 yds. (3600") indicated by the
proportion .00l· pi /10=X/3600, from
which x =1.1".

As a practical matter, runout up to .003 has no discernible impact on group sizes at 1000 yds.

 

[CaptArab]

Redding body (or fl bushing sans bushing) plus Lee collet is a good way to get up to speed on any bolt gun.

 

[Clark]

As a practical matter, runout up to .003 has no discernible impact on group sizes at 1000 yds.

I learned that my intuition about errors adding is wrong.
I designed and amplifier that was mass produced and computer tested.
With ~ 50 resistors with 0.5% accuracy involved in gain calculation, I calculated gain could vary from -15 to + 50.
But production showed the Gaussian distribution inside the nominal gain =10 with +/- 5% accuracy.
It seems errors cancel more than they add.

Just because I cannot measure the effect of some handloading accuracy ritual, doesn't mean it has no effect.
So the process I choose from the many accuracy rituals is not with controlled experiments... it is by intuition, anecdotes, and fads...anything but science.