Best concentricity sizing method I have used

H

hounddawg

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My latest method for getting minimal runout

1. Start with new cases or cases that have been resized in a FL non bushing die

2. Perform a 95% skim neck turn using your neck turning tool of choice. I like the Hornady but any will do the trick if properly used

3. Full length resize the case using a non bushing die with the expander button removed. Any FL die will do, even the budget Lee

4. Expand the neck with a mandrel to get your preferred ID for neck tension. I use a Sinclair Gen II mandrel die with Twenty first Century mandrels. Currently the Sinclair is not available for order. However the 21st Century holder is the almost the same price. I prefer mandrels .003 smaller than the bullet diameter for everything. Once again though that is a matter of personal choice, some like more compression some less. They are available in .0005 increments so you could try several if you want.

That is all there is to it. I am getting .001 runout or less on 99.9% of my loads by using this method. I have tried it on .260 Remington, 6.5 Grendel, and 6BRs so far and had great results on all three. Between this and starting to anneal again, I have just about eliminated my "what the heck" flyers on my developed loads

link to 21st century mandrels

http://www.xxicsi.com/caliber-specific-expander-mandrels.html

link to 21st Century expander holder die

http://www.xxicsi.com/expander-die-body.html

You can argue about whether concentricity makes a darn or not but I think

 it helps to eliminate flyers. Key word there is think.
 
People have shot half MOA 10 shot groups at 600 yards with 308 Winchester ammo having .004 inch bullet tip runout.

Remember that cartridge spinners don't align cartridges to dial indicators like they are to bore centers.
 
That's a good alternative to the two-die (Lee collet and reading body) method for handling sizing. Everyone I know who got tired of the pull-through expanders tipping their case necks has gone to mandrels because a conical shoulder is much stronger resisting being pushed down than when being pulled up, so it tends to hold shape at its junction with the neck better. I will mention though, that in 30-06 I ran the Redding carbide expander for a long time and it didn't seem to pull necks off-axis like the steel buttons do, either. Less friction with the harder carbide and shorter contact area. I did, additionally, use a dry inside neck lube even with the carbide.

Regarding the effect of misaligned bullets, it varies enormously with the bullet design. Longer bearing surfaces with the CG closer to the center of the bearing surface are least affected. A. A. Abbatiello got about half a moa of drift away from the group centers (1 moa group widening) with the NM M1 Type bullet tilted 0.004", while Harold Vaughn got less than half that (3/8 moa groups from a one-holer integral machine rest gun) with more squat flat base 6 mm bullets. Vaughn identified the high point on each round and fired 8 of them rotating 90° in the chamber for each round. It printed a quad of double-holes. I made one to match what Abbatiello's reported variation with the M1 Type would do in that same test. One of the lessons was that if you can orient your tilts the same way in the chamber each time, the effect appears only as an offset in your sight settings.
 

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Regardless of whether concentricity matters or nor all I can say is that making them concentric is working for me. Prior to starting back annealing and changing my sizing method appx 1 out of ten shots would be a non called vertical flyer. Those have pretty much been eliminated.

As far as my choice of concentricity tools go, if the bullets are landing in the ten ring it really does not matter does it ? Now if they just invent a tool that will eliminate that the crosswind at 500 yards
 
A consistent and properly loaded round will beat a non consistent and properly properly loaded round in the hands of the same shooter and rifle regardless of the discipline.

That is why I reload, and do not shoot factory ammo
 
Hounddawg, it's really pretty simple, isn't it. I go with only .001" tension on the bullet because it seems to be easier to align the bullet. I try for .001 runout on the finished bullet alignment.
Unclenick, all my loads have a black mark on the neck for proper placement in the chamber. It does make a difference.
 
Hard to argue with success, and am firm believer in concentric/consistent is one of the best things to get in from selected handloading procedure. And not just the mechanical accuracy, but the confidence.
 
Of course,accuracy is good.
Someplace I have Precision Shooting's book "Handloading for Competition"

It spoke of "Pretty good ammo". Which is ammo that does not limit the shooter.

The point being time and effort in the loading process,and less ammo loaded,versus more ammo and more practice. There is a point of diminishing returns.You get to decide where that is.

The book suggested two things for concentricity. Snug down your lock ring ram up,die under load. And

Use a rubber O-ring under your lock ring.

It also suggested brushing ID of the neck,with some dry lube on the brush.

I don't doubt extra measures make a difference. I'm just not a good enough shot to realize the gain from less ammo,more precision versus pretty good ammo,more practice.

You get to decide!
 
Why snug down your lock ring ram up, die under load over the rubber O-ring?

Regarding cartridge concentricity and measuring it, depending on the gauge and how it's set up, a given cartridge can have different runout numbers.

Unclenick, please show us your picture with different setups.
 
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It was the advice given by a pretty credible source.Its been years since I read it. They did do some runout testing to confirm it helps.
I give the Precision Shooting book credibility in similar fashion to giving you,Bart,or Unclenick credibility.There is a "Been there,done that" factor.

But I'll hazard a guess.In a way,a vee thread can act as a helical vee block.
If its free to center,it will try to center under end load.

The o-ring will prevent rotation while allowing some float.

Maybe along the lines of the Bonanza Co-Ax press idea.

But I can't give a definite answer.
 
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"It was the advice given by a pretty credible source.Its been years since I read it. They did do some runout testing to confirm it helps.
I give the Precision Shooting book credibility in similar fashion to giving you,Bart,or Unclenick credibility.There is a "Been there,done that" factor."


Sounds like "squaring" your dies, which is a documented procedure in numerous older loading manuals and a certain military shooting team. These references were previously provided. However some here are not believers, as is their opinion. And yes you can tighten up a sizing die slightly off perpendicular. It costs absolutely nothing to square up your die. Only an individual can determine whether it is a benefit to your specific loading procedures/purpose.
 
I honestly don't think squaring the dies has much to do with it if you are using a full length non bushing sizing die. When that piece if brass is fully enclosed in the die it has no choice except to be concentric.

Some things I think lead to non concentric necks

- bushings being pulled back through the necks when they are unsupported by the interior walls of the die

- cases which have uneven brass thickness in the neck area

- cases which have a raised lip just at the mouth of the case. This can only be cured by taking .001 - .002 off the OAL of the case by trimming.

I seat on a Lee Turret press, lots of float in those turrets. This morning I seated 50 rounds of 6BR using 68 gn Berger flat base bullets. I used a Frankford Armory Universal seating die. Lots of float in both the press and the case sitting in the seating die yet the runout was minimal. About 10 % of the 50 had runout greater than .0005, the maximum runout on all 50 was .0015.

As far as whether you will notice a difference if you can consistently put 9 rounds into a nice tight .5 to .75 MOA circle on a windless day and the 10th is a uncalled vertical flyer. That would be using a target style rifle with a decent barrel on a good rest or bipod& bag. If that happens on a regular basis the that is the ammo or the barrel not the shooter. In my opinion that is when you need to start putting that extra effort into the ammo. Turning the necks, annealing the brass, taking a look at your sizing techniques etc etc
 
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hounddawg said:
I honestly don't think squaring the dies has much to do with it if you are using a full length non bushing sizing die. When that piece if brass is fully enclosed in the die it has no choice except to be concentric.
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Would agree with the brass that is fully enclosed in body of the die. Would not agree that means any brass outside of the die is concentric with the brass inside of the die, which is the point being addressed by squaring your dies.

https://www.sierrabullets.com/reload-basics/resizing-depriming/

"Squaring Dies

One facet of die adjustment that is seldom mentioned is “squaring “ the die The industry standard for reloading dies is a 7/8 x14 thread. Virtually all U.S. reloading equipment manufacturers thread dies and presses for this pitch. This is coarse enough to allow for fairly rapid die installation and removal in reloading presses, but is still fine enough to maintain a good degree of precision and alignment in assembly. Unfortunately, in many instances, there will still be some misalignment between the ram/shell holder and the die body.


Carbide dies, such as this Titanium Carbide set from Redding, eliminate the requirement for lubricating straight-walled cases prior to sizing.

To square your dies, start by following the adjustment procedures outlined above, up to the point of locking the die. Rather than merely snugging the lock ring down against the top of the press and locking it, the dies are squared by lowering the ram slightly, and placing a flat machined washer between the die body and the shell holder. Raise the ram slowly, until the washer is putting light to moderate pressure on the bottom of the die. This will remove the play from the threads, while the flat washer helps to hold the die body square against the shell holder. Maintaining pressure on the die body, now lower the lock ring, and lock the die firmly in place.

This procedure applies to both sizing and seating dies, but should not be used with either carbide sizing dies or benchrest/competition seating dies. You will find that dies that have been squared in this manner will be somewhat difficult to remove from the press. If the lock ring must be loosened to remove the dies, simply repeat the process the next time you set up to reload. The time this procedure takes to perform is minimal, and we feel the results are well worth the effort."
 
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old roper said:
I'd like to see some groups Bart/Nicks have shot. Target with bullet holes.
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Shots 1 and 2 are first ones from a clean barrel.
 
On the squaring of the die. There is not much brass outside the die when on the top of the stroke, a bit of the web, the rim and case head is all.You can't really get a press with much more float than the Lee Turret, yet that is what I use and with decent results

Here is a target illustrating what I was talking about in the post above.This was shot from a practice rifle, Savage FTR with aftermarket Shilen barrel in 260 Rem. No bedding, stock accutrigger. This is a 600 yard target with a 6 inch ten ring shot at 835 yards.

Nine of ten shots are in a fair group however the shot with the arrow is way down in the 8 ring a good 8 inches lower than the main group. Now that could have been a dozen things with my technique wise but I did not feel like it was any of them.

This was a from a practice session just before I started annealing again and I have since switched over to using non bushing dies with a expander mandrel. Just those changes have pretty much eliminated those what the heck flyers for me. I will drop the occasional shot but those are wind related or me putting my finger inside the trigger guard too early
 

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I have never blamed anyone but myself for a bad shot . I win Benchrest at 100 and 200 yards , and I could never say I was 100 percent certain my equipment or loads have failed me . This of course is after fully working up a load and it proving itself in a match . I don't believe anyone can that actually touches that trigger without an artificial aid can say they are better than that load. Way too many variables involved, human error is something some folks just can't admit . This coming from a guy that hates it when a flier opens my group to .250" at 100 .
 
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