Bullet Runout Issues - Help!

[Kracken McGraw]

Since both of your rifles can shoot factory ammo, did you rule out flyers by shooting the factory rounds?

 

[dellet]

Just a couple more thought, no load data mentioned, is it possible you’re seating the bullet past the duuuuuuhnut?

What has changed since April that might cause your runout to change, basically double?

Thread 'Bullet Concentricity/Runout'

Apr 28, 2025

Hi all, I upgraded my whole reloading setup recently and just got everything set up. Using an Amp Annealer, Amp Arbor Press, Short Action Customs Infinity in-line Seating Die, Area 419 Zero Gen II press (for sizing), Area 419 M series FL sizing dies, Accuracy One Concentricity gauge, and Henderson Trimmer.

I'm trying to squeeze every little bit of accuracy out of my rounds. I know all this isn't necessary, but it's my hobby and I enjoy trying to chase every minuscule imperfection.

I recently loaded up some new cases (Peterson) and am not thrilled with the bullet Concentricity. I got...

• cjc5062
• Replies: 34
• Forum: Reloading Forum (All Calibers)

• 

 

[6BRA]

For those that say...Freebore will straighten it out.
let me ask.....

If a bullet with .005 to .008 runout is placed in the Freebore. What happens to the cartridge case that you have set perfect headspace for? For every action there is a reaction. I set my headspace at about .002. This allows my case to float in the chamber. However....if everything isn't in align. Something is going to have to give. So to be dramatic and illustrate what I am saying. If you take a loaded round with .008 runout and load it into the chamber/freebore and close the bolt. Wouldn't the case be torqued or in effect not free float or not present itself against the bolt face square? Just asking.

 

[jelenko]

The break was .003 this time and I could discern no difference.

I've seen the same result from other top shooters.

 

[dellet]

For those that say...Freebore will straighten it out.
let me ask.....

If a bullet with .005 to .008 runout is placed in the Freebore. What happens to the cartridge case that you have set perfect headspace for? For every action there is a reaction. I set my headspace at about .002. This allows my case to float in the chamber. However....if everything isn't in align. Something is going to have to give. So to be dramatic and illustrate what I am saying. If you take a loaded round with .008 runout and load it into the chamber/freebore and close the bolt. Wouldn't the case be torqued or in effect not free float or not present itself against the bolt face square? Just asking.

It depends on chamber diameter clearances. Once there is enough bend in the cartridge where there are three solid points of contact, the chamber act like a Hornady concentricity tool and bends the cartridge at its weakest point. Generally the bullet in the case mouth.

This is where jam and jump can make the answer different. A bullet that jumps into the freebore has a chance to to self align, two tapers tend to align themselves. Shape of the ogive comes into play. That’s why some shapes are easier to tune than others.

A cartridge touching hard at 3 points because of excessive bullet runout, say side of the bullet, shoulder, case head is already lined up to do a bank shot into the bore.

It’s a floating scale, but it’s pretty safe to say that if you have clickers while trying to chamber a round because the chamber is used to straighten out a bent cartridge, it probably will show up on target.

 

[K22]

I’ll get a flyer once ever 3-4 shots. My SD is always in the single digits and ES in the mid to high teens typically. Shooting gunwerks rifle for both 6.5 PRC and 7PRC

The only time I ever experienced consistent flyers in centerfire rifles with reloaded ammo I traced to two causes:

1. Bedding issues and / or barrel contact with the stock.

2. Cleaning with aggressive strong copper remover solvents - requiring several shots to re-establish desired POI.

I never traced a consistent flyer situation to bullet run out. This does not include an isolated case of a Rem 700 that had, as confirmed by Remington, a barrel with defective rifling.

Just my experience, not making any general pronouncements.

 

[Murray Brook]

If you want to ,get your run-out down then an inexpensive way to do it is to size your case with a Redding body die then size your case neck with a Lee collet die . Seat your bullet with a good seater die like Foster, Redding etc. Your run-out will be low if you are using good brass. JMO

 

[ronemus]

Until you have neck-turned your brass and fireformed it in a correctly machined chamber, you won't be able to get low runout. Think about the reloading process - you size the exterior of the case, but if neck thickness isn't uniform then bullets won't be aligned with the centerline of the case. At a minimum you'll have to turn necks and fire them at least once before you'll be able to get low runout.

An Autodod is overkill for most purposes, and if you're doing small volumes a conventional neck turning kit is more than sufficient. Be sure to get carbide cutters that are a match for the shoulder angle of your cases, and carbide mandrel sets (matched expanding and turning, usually 0.001" different diameters). Neck turn after expanding necks as this will move the donut to the outside of the neck where it will be removed by turning.

I load a fair volume because I'm a competitive Highpower shooter, so I try to make my process as efficient as possible. I use Hornady sizing dies with the elliptical expander, which gives me good runout and eliminates a separate expansion step.

Seating dies that use a sliding sleeve give me the best runout, and Forster dies have been the most durable for me - the shape and metallurgy of the seating stem are the best I've tried, and the geometry works with the pointiest bullets I've used.

Be sure to anneal before sizing, because I've proven to myself that annealing afterwards destroys concentricity.

Imperial Sizing Wax (or some of its imitators) is the way to go as it is very slick and and can be used sparingly - a barely visible film under good light. Unfortunately it makes for a 2-step lube process: apply to exterior (including neck and shoulder) with fingertips, and inside the neck with a cotton swab. Done properly there are never lube dents and all sizing is smooth and easy - if it feels rough it won't be consistent.

Use a concentricity gage to set up and refine your loading process, and check results after each step until any issues are resolved. Then put it on the shelf and check every once in a while for QC. If you have to use it to sort loaded rounds or components you're doing something wrong.

I've refined my process to the point that I produce rounds with runout of 0.003" or less measure near the tip of the bullet. I use a Sinclair gage and support the case near the base and shoulder when measuring. It's frustrating to read posts with runout numbers and no definition of what and how they are measured.

 

[Bill Norris]

This thread just made me do something I have not done in quite awhile. I took the Sinclair concentricity gauge down and blew the dust off to check a few 30BR loads that I loaded a few nights ago. Measured 10 rds. and had total of .001 variances. 7 of the 10 were virtually at zero to .0005. Back years ago when I used to dwell on it I learned handling of the press handle could play a huge part in reducing runout. Just because you may have a heavy hunk of steel (press) that can mutilate a simple piece of brass don't mean you have to act like you want to destroy it. LOL.

 

[falconpilot]

Several have touched on it here, but a good inline seat cured any runout problems I’ve had..all I use now..

 

[cjc5062]

Until you have neck-turned your brass and fireformed it in a correctly machined chamber, you won't be able to get low runout. Think about the reloading process - you size the exterior of the case, but if neck thickness isn't uniform then bullets won't be aligned with the centerline of the case. At a minimum you'll have to turn necks and fire them at least once before you'll be able to get low runout.

An Autodod is overkill for most purposes, and if you're doing small volumes a conventional neck turning kit is more than sufficient. Be sure to get carbide cutters that are a match for the shoulder angle of your cases, and carbide mandrel sets (matched expanding and turning, usually 0.001" different diameters). Neck turn after expanding necks as this will move the donut to the outside of the neck where it will be removed by turning.

I load a fair volume because I'm a competitive Highpower shooter, so I try to make my process as efficient as possible. I use Hornady sizing dies with the elliptical expander, which gives me good runout and eliminates a separate expansion step.

Seating dies that use a sliding sleeve give me the best runout, and Forster dies have been the most durable for me - the shape and metallurgy of the seating stem are the best I've tried, and the geometry works with the pointiest bullets I've used.

Be sure to anneal before sizing, because I've proven to myself that annealing afterwards destroys concentricity.

Imperial Sizing Wax (or some of its imitators) is the way to go as it is very slick and and can be used sparingly - a barely visible film under good light. Unfortunately it makes for a 2-step lube process: apply to exterior (including neck and shoulder) with fingertips, and inside the neck with a cotton swab. Done properly there are never lube dents and all sizing is smooth and easy - if it feels rough it won't be consistent.

Use a concentricity gage to set up and refine your loading process, and check results after each step until any issues are resolved. Then put it on the shelf and check every once in a while for QC. If you have to use it to sort loaded rounds or components you're doing something wrong.

I've refined my process to the point that I produce rounds with runout of 0.003" or less measure near the tip of the bullet. I use a Sinclair gage and support the case near the base and shoulder when measuring. It's frustrating to read posts with runout numbers and no definition of what and how they are measured.

Thanks for the good info. I’ve been running new Peterson brass but am going to try some fire formed brass this week to experiment with.

Do you recommend a particular neck turner? I’ve read pros and cons of lots. Would rather not spend money on autodod.

Good news though is I found a good powder charge today for my both 6.5 PRC and 7PRC that was shooting .25 MOA at 100 for both. Found good nodes and seating depths over the last week.

But still want to get the runout issue solved for my own knowledge that I’m doing everything as best as possible.

 

[cjc5062]

Thanks guys for all the good info. I really do appreciate it.

Going to run some tests this upcoming week and try some of the suggestions on this post.

 

[jelenko]

Until you have neck-turned your brass and fireformed it in a correctly machined chamber, you won't be able to get low runout.

I disagree. Please see my post #57 above.

I never.never neck turned my brass, I have paid no attention to fireforming. I do assume the gunsmiths who have chambered the barrels I use do it well.

I have never found more than .002 run out with 99.99% .001 or less.

 

[muleystalker]

Stop annealing new brass before it's fired, it's already been annealed. Unless you are forming cases for a wildcat or something where you are manipulating the brass in several procedures.

 

[Fire Dog]

Just a couple more thought, no load data mentioned, is it possible you’re seating the bullet past the duuuuuuhnut?

What has changed since April that might cause your runout to change, basically double?

Thread 'Bullet Concentricity/Runout'

Apr 28, 2025

Hi all, I upgraded my whole reloading setup recently and just got everything set up. Using an Amp Annealer, Amp Arbor Press, Short Action Customs Infinity in-line Seating Die, Area 419 Zero Gen II press (for sizing), Area 419 M series FL sizing dies, Accuracy One Concentricity gauge, and Henderson Trimmer.

I'm trying to squeeze every little bit of accuracy out of my rounds. I know all this isn't necessary, but it's my hobby and I enjoy trying to chase every minuscule imperfection.

I recently loaded up some new cases (Peterson) and am not thrilled with the bullet Concentricity. I got...

• cjc5062
• Replies: 34
• Forum: Reloading Forum (All Calibers)

• 

Ahhhhh Doh-nuts….

 

[chromatica]

Here are the practices that allow me to minimize runout:

• I use a Co-Ax press.
• I use the Co-Ax one-piece jaw module.
• I use elliptical-head screws to retain the jaw module. The conical underside of the screw head will self-center the jaw module.
• I adjust the conical jaw-stop so that there is a small gap between the jaws at the bottom of the stroke. This ensures that the case head is centered at the beginning of the stroke.
• I use a Wilson FS sizing die with a bushing. I make sure there is enough room in the top of the die for the bushing to rattle.
• I use Sinclair cross-bolt die lock rings. They provide an interference fit for the Co-Ax press resulting in less slop than with the Forster, Lee or Hornady die-lock rings. In addition, Sinclair rings are made out of steel – not aluminum.
• I orient the die so that the seam in the ring is fully supported in the slot. I don’t want the ring to distort under load.
• I use a Lee Collet die after FS sizing so that the last operation on the neck is an expansion - giving me .002 neck tension
• I use a Forster Ultra Micrometer seating die.
• I put a chamfer on the inside of the case mouth as part of the trimming operation, so that the base of the new bullet moves easily down the neck.
• Use three partial strokes to seat a bullet, rotating the case 120 degrees after the first and second stroke. The third stroke reaches the limit of travel.
• I do not crimp!
• I measure my runout about 3/16 inch above the case mouth on a Hornady Concentricity Gauge at +/- .0005

 

[ELR LVR]

Hi all, so I’ve completely gone off the deep end the last few months with precision hand loading. I don’t shoot PRS or anything, but do go out west to hunt every year and shoot often. I enjoy trying to get the most precise loads and accuracy out of my hunting rifles and am just trying to learn as much as possible. I’m focused on 6.5 PRC and 7 PRC at the moment.

In the last few months I have completely upgraded my reloading set up. I’m now running the following setup: Area 419 Zero 2 Press, Area 419 Full Length Micrometer Sizing Dies, Short Action Customs Infinity Arbor Seating Die, Amp Mark II Annealer, Amp Press, Henderson Trimmer, Primal Rights Primer, Ingenuity Precision Powder Trickler with Sartorius Scale, Mitutoyo calipers, Mitutoyo micrometer, Area 419 comparator set, Area 419 Powder Funnel and tube extensions, Accuracy One Concentricity Guage with Mitutoyo dial, and other odds and ends items. I have not yet purchased an Autodod case neck turner, but it has crossed my mind.

I have watched just about every video I can out there, including Primal Rights, Ultimate Reloader, Bolt Action Reloading, F-Class John, etc. and have tried my best to use the same processes in start to finish reloading. I’m currently using new Peterson Brass (sorted to .005” - <.001” neck concentricity), anneal first, then trim/chamfer, brush inside of the neck with nylon brush, powder charge, seat bullet.

I have been able to get down to very good Standard Deviations in my loads (some as low as 3 fps Standard Deviation for 3 shot groups), but cannot for the life of me get consistent or acceptable bullet runout. I’m using Berger Elite Hunter bullets in 140gr. for 6.5 PRC and 175gr. for 7PRC. I take my measurement of bullet runout halfway between the neck of the case and end of the bearing surface (before bullet starts to angle down). My bullet runout measurements range anywhere from .002” to .008”. With the quality of components and tools I’m using, I’m really hoping to get the runout to around .0005” but at this point would take anything less than .002”. I think I may have narrowed this issue to a few things, but would like to get other’s thoughts before I go trying other things:

1. Short Action Customs Seating Die – I’ve heard mixed reviews on the SAC Infinity Die, in that there is too much movement since it is made for any caliber. Thinking of trying Micron dies or anything else that is highly recommended for precision.
2. Henderson Trimmer – The pilot on the Henderson trimmer, while it doesn’t seem to do much to the inside of the neck when trimming/chamfering, I know Primal Rights states the pilot trimmers can impact seating. Although, I know this trimmer is highly regarded by many and used without issue.
3. Change the lubrication for sizing – I currently use Hornady One Shot for lubrication, but this does not necessary get inside the neck well. I’ve heard many shooters using imperial wax as the main lubrication of choice.
4. Neck turning – I have not yet purchased a neck turner, although I’m considering an Autodod. However, in watching various videos, I know getting <.002” bullet runout is very doable without neck turning.

Please let me know if there is anything that stands out to anyone, or if there is something I’m not thinking of. I know bullet runout may not impact accuracy all that much, but its more about the pursuit of trying to get the most out of my loads. It’s also just driving me absolutely crazy lol

What brass you using?
Lapua gives me the highest amount of neck tension
Peterson is smoother with less tight neck tension
Use a nylon brush inside the neck when sizing, and roll it in Mink Oil Paste for boots
To further customize things, Use a bushing die and experiment with different sized bushings
from .001" to .003" neck tension
If your brass is hellaciously resistent to stretching (Lapua) you may want a .001" under bushing
If it acts like Remington (My favorite) or Peterson brass, you may want .002" to .003"
--------------------------------------------------------
My first thought is - Too much neck tension
one side of your shoulder could be collapsing -
(Too much neck tension along with soft annealed shoulders)
2nd thought is, not turning your necks to be equal thickness all the way around
3rd thought is - Using something that straightens the neck out when you size it helps tons
Hornady makes a long tapered type expander vs a ball button
this straightens out the neck very well
others use a mandrel for the same thing
Your neck has to start off straight
--------------------------------------------------------
I measure my runout wayyyyyyyy out there near the tip of the bullet and when all things are correct
it is usually not more than .001"
Tight brass is the only brass that has ever given me trouble, because it wants to spring right back to the way it was (memory)
BTW, between .012" & .013" neck thickness is a good number for larger cases
Use a .0001" resolution ball mic for this, not your calipers
--------------------------------------------------------
+1 for Redding or Forster Micrometer Competition Bullet seaters
You can spend more for nicer, but they aint gonna be any better
-------------------------------------------------------
You may still get a few rounds over .005" runout until everything has been shot and fireformed a couple times and you burn in the memory of the case and neck being straight
Use them as foulers, You may be surprised how well those foulers shoot

 

[TxBowHunter409]

A lot of us with less desirable seating dies rotate the case several times while seating the bullet in small increments. It’s a idea that has been handed down in this Forum and seems to help in run out

I do exactly the same thing. Probably a ¼ to a ⅓ of a turn each time. Might not make a hill of beans difference, but it makes me feel good about it.

 

[TxBowHunter409]

Hi all, so I’ve completely gone off the deep end the last few months with precision hand loading. I don’t shoot PRS or anything, but do go out west to hunt every year and shoot often. I enjoy trying to get the most precise loads and accuracy out of my hunting rifles and am just trying to learn as much as possible. I’m focused on 6.5 PRC and 7 PRC at the moment.

In the last few months I have completely upgraded my reloading set up. I’m now running the following setup: Area 419 Zero 2 Press, Area 419 Full Length Micrometer Sizing Dies, Short Action Customs Infinity Arbor Seating Die, Amp Mark II Annealer, Amp Press, Henderson Trimmer, Primal Rights Primer, Ingenuity Precision Powder Trickler with Sartorius Scale, Mitutoyo calipers, Mitutoyo micrometer, Area 419 comparator set, Area 419 Powder Funnel and tube extensions, Accuracy One Concentricity Guage with Mitutoyo dial, and other odds and ends items. I have not yet purchased an Autodod case neck turner, but it has crossed my mind.

I have watched just about every video I can out there, including Primal Rights, Ultimate Reloader, Bolt Action Reloading, F-Class John, etc. and have tried my best to use the same processes in start to finish reloading. I’m currently using new Peterson Brass (sorted to .005” - <.001” neck concentricity), anneal first, then trim/chamfer, brush inside of the neck with nylon brush, powder charge, seat bullet.

I have been able to get down to very good Standard Deviations in my loads (some as low as 3 fps Standard Deviation for 3 shot groups), but cannot for the life of me get consistent or acceptable bullet runout. I’m using Berger Elite Hunter bullets in 140gr. for 6.5 PRC and 175gr. for 7PRC. I take my measurement of bullet runout halfway between the neck of the case and end of the bearing surface (before bullet starts to angle down). My bullet runout measurements range anywhere from .002” to .008”. With the quality of components and tools I’m using, I’m really hoping to get the runout to around .0005” but at this point would take anything less than .002”. I think I may have narrowed this issue to a few things, but would like to get other’s thoughts before I go trying other things:

1. Short Action Customs Seating Die – I’ve heard mixed reviews on the SAC Infinity Die, in that there is too much movement since it is made for any caliber. Thinking of trying Micron dies or anything else that is highly recommended for precision.
2. Henderson Trimmer – The pilot on the Henderson trimmer, while it doesn’t seem to do much to the inside of the neck when trimming/chamfering, I know Primal Rights states the pilot trimmers can impact seating. Although, I know this trimmer is highly regarded by many and used without issue.
3. Change the lubrication for sizing – I currently use Hornady One Shot for lubrication, but this does not necessary get inside the neck well. I’ve heard many shooters using imperial wax as the main lubrication of choice.
4. Neck turning – I have not yet purchased a neck turner, although I’m considering an Autodod. However, in watching various videos, I know getting <.002” bullet runout is very doable without neck turning.

Please let me know if there is anything that stands out to anyone, or if there is something I’m not thinking of. I know bullet runout may not impact accuracy all that much, but its more about the pursuit of trying to get the most out of my loads. It’s also just driving me absolutely crazy lol

LOL.. God you sound so much like myself it's scary. I too have just gone off the deep end into reloading. To the point my wife says I shoot just to be able to reload. I tell her it's the other way around, but really she might actually be right. It's the challenge of being able to get a normal firearm to shoot the absolute best that's my driving force. And like yourself, the 6.5 PRC and the 7mm PRC are probably my favorite two firearms to reload and shoot. And I'm at the range at least a couple of times a week. My wife just tells me I'll see you at dark

I too have upgraded my reloading gear as I've gone. Only recommendation I can make in your very impressive list of equipment, is don't let yourself get totally caught up in the name game. Just because it's more expensive, doesn't necessarily make it better. Stick with what's working the best for you.

But since we're discussing gear and tricks, here's mine:

* Forster Co-Ax press
* Forester full length bushing sizing dies exclusively with the expander ball and decapping rod removed.
* Short Action Customs comparators.
* Mitutoyo calipers
* Burstfire annealer
* Ugly SRT trimmers for each caliber I reload
* Frankfort Arsenal wet tumbler. (¼ teaspoon of Lemishine, healthy squirt a Dawn, and 5 pounds of ⅛" stainless slant cut tumbling media). Run for no more than 1½ hours to prevent rolling the necks over. Towel dry exterior after separating media to prevent water spots, then 4 hours in a cheap Amazon dehydrator set at 158⁰ to dry.
* Lyman funnel kit (I just need the powder in the case. They work fine for that).
* I think it's a Redding Universal Decapping die. The one in the green case.
* Imperial Sizing Wax for sizing
* L.E. Wilson mandrel die
* Imperial dry case neck lube. I dip the case neck into the dry lube twice before running through the mandrel die.
* Yellow Box Elite Hunter bullets in both PRC's. 140 grain for the 6.5, and 175 for the 7.
* VihtaVuori N568 powder in both guns.
* K&M Arbor Press
* L.E. Wilson inline seating press. Again, one for each caliber I reload, with VLD stems for the Bergers.
* RCBS MatchMaster powder dispenser.
* Accuracy One bullet seating comparator. (Heard about this from F-Class John and it is the bomb. Measures seating depth using shoulder to ogive instead of base to ogive).
* I dip my bullets in the Imperial dry case neck lube before seating.
* Peterson brass for the PRC's. Lapua brass for everything else.
* CCI primers exclusively
* Frankfort Arsenal case prep center using VLD inside chamfer bit and 4 blade debur bit for the outside. Only thing I use that station for.
* When I still used the Forster Ultra Micrometer Seating die, I'd give it a full stroke, turn the bullet ¼ to ⅓ of a turn, and a second full stroke. I still use the Forster seating die when doing seating depth test simply because it's easier.
* I use a Larry Willis collet die set up permanently in a Rock Chucker press when sizing my 300 Win Mag, just to control belt swell on the magnum cartridges.
* Garmin Chrono
* Dental office vibrating plate to settle powder when loading powder at or near case capacity.

Well that's about all I can think of at the moment I guess. Although as soon as I hit post, I'll think of something useful I should have said. Good luck with the quest!