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Bullet run out how much matters?

Cast bullets here at starting JB velocity.

Two things that immediately showed up on paper was/are.... annealing and getting deadnuts straight ammo. The former is harder to quantify because if you're getting good performance and repeatability withOUT annealing.... cool. Hard to argue. What's easier to explain,because it shows up so much better on a cast bullet.... is runout. The launch cycle of cast has to be controlled to the umpteenth degree. Ya'll think bench manners matter shooting JB's..... try that devided by ten. Things like screw torque, depending on the rig,may or may not show up on paper..... with cast it's a heck of a lot more apparent. So,the same for runout.

A well behaved rig/load/tune that will hold it's own in the wind..... these are med hard jams. It's dang obvious on paper what straight ammo will produce. It gets lost in the noise with jacketed.... best I can tell. It's more dependent on a particular rig than any blanket statement can be proved or not.
I could see this mattering more with cast bullets. They would get distorted way easier. Matt
 
Are there ANY,.. "fixes" for .005-.010 bullet "runout" issues ??? Would, a Lee Collet, crimp Die,.. HELP, this ???
Do I need to throw my RCBS Dies,.. in the Trash and BUY Redding Type "S" collett Dies ?? HELP !!!
 
Cut the barrel off at the chamber mouth first.

Used dead primed 308 cases in a "chambered" action, very straight cases with headspace a few thousandths less than chamber. With the extractor and striker spring removed, the case mouth would rest off center in the chamber mouth until the striker/firing-pin, or in line ejector, pushed the case forward centering its shoulder in the chamber shoulder. Case mouth went from off center to dead center or a smidgen opposite case head. Couple thousandths uniform clearance around case necks and mouths. Used a 10X loupe to easily see details.
Thank you,
I wasn't sure how you would do that but now I know.
 
Are there ANY,.. "fixes" for .005-.010 bullet "runout" issues ??? Would, a Lee Collet, crimp Die,.. HELP, this ???
Do I need to throw my RCBS Dies,.. in the Trash and BUY Redding Type "S" collett Dies ?? HELP !!!
Wow "
That's a lot of run out.
 
Wow "
That's a lot of run out.
YUP and I'm piszzed oft about it, BUT am getting, .280 ( 3 shots ) to sub, 1/2 MOA ( 5 shots ) groups from my Tikka T3 .243 win. loaded with, the 80 grain, Sierra #1515 Blitz's @ 100. I believe the problem lies with the Expanding Ball pulling thru the "Neck" after FL sizing, I lube the necks lightly and have polished the Exp Ball. I have also, polished/ lapped, the Seat Plug to "fit" my Bullets, so I don't think it's a Bullet seating issue. NOT all the loads are that, "BAD" but more than, I'd like !!
 
YUP and I'm piszzed oft about it, BUT am getting, .280 ( 3 shots ) to sub, 1/2 MOA ( 5 shots ) groups from my Tikka T3 .243 win. loaded with, the 80 grain, Sierra #1515 Blitz's @ 100. I believe the problem lies with the Expanding Ball pulling thru the "Neck" after FL sizing, I lube the necks lightly and have polished the Exp Ball. I have also, polished/ lapped, the Seat Plug to "fit" my Bullets, so I don't think it's a Bullet seating issue. NOT all the loads are that, "BAD" but more than, I'd like !!

First you need to find out which reloading step is starting the runout. Yes expander buttons are a pos and shouldnt be used. Try a fl bushing die with no expander
 
First you need to find out which reloading step is starting the runout. Yes expander buttons are a pos and shouldnt be used. Try a fl bushing die with no expander
I just read bozo 669's post from 2013 and that was his solution, too ! THANKS, Dusty,.. I will try it that, way !
 
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Are there ANY,.. "fixes" for .005-.010 bullet "runout" issues ??? Would, a Lee Collet, crimp Die,.. HELP, this ???
Do I need to throw my RCBS Dies,.. in the Trash and BUY Redding Type "S" collett Dies ?? HELP !!!

Wow "
That's a lot of run out.
I've chucked 7.62 M118 match ammo necks in a .338 caliber bullet puller then pressed its body back straight to less than .003" runout. Cases were marked at runout high point to show runout; "6" at the. 006" runout side. A little practice led to usually getting it back to tiny on first try. Those bent too far got bent back the other way.

M118 match case necks inside were a thousandth or more larger than the FMJBT match bullet. It was smeared with black sealant and some bullets ended seated very crooked after the sealant dried. Same with M852 ammo with Sierra 168's.

If resized case necks are straight on the case shoulder and body, bullets seat much straighter. Hone those RCBS die necks to 1 to 2 thousands smaller than that of a loaded case neck. Toss the expander ball.
 
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YUP and I'm piszzed oft about it, BUT am getting, .280 ( 3 shots ) to sub, 1/2 MOA ( 5 shots ) groups from my Tikka T3 .243 win. loaded with, the 80 grain, Sierra #1515 Blitz's @ 100. I believe the problem lies with the Expanding Ball pulling thru the "Neck" after FL sizing, I lube the necks lightly and have polished the Exp Ball. I have also, polished/ lapped, the Seat Plug to "fit" my Bullets, so I don't think it's a Bullet seating issue. NOT all the loads are that, "BAD" but more than, I'd like !!
I would never use an expander ball. I use a expanding floating mandrel when mecessary
 
Theoretically (and in reality) it matters. Crooked bullets don't fly in the same direction straight bullets do. This is a major source of dispersion.

Practically, if your process and equipment are correct (which isn't hard - it takes no special tricks - just properly lube your (good) cases and use appropriately sized bushings/dies, and skip the expander), you won't have enough runout to matter unless your equipment is defective. To give a number, you have to specify how you're measuring "runout", which sometimes is an inaccurate term for what people are actually measuring.

Buying a runout gauge just told me that I don't need a runout gauge. This makes me wonder why I don't sell mine...
 
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I have watched case mouths and necks center in chambers from firing pins pushing on primers in case heads.

And watched case mouths move in chamber mouths opposite that of case pressure rings.

The barrel was cut off at the chamber mouth first.


I believe you misunderstood, the testing I was referring to is similar to what Preacher did in post 16 but with a larger sample and shot from a machine rest to eliminate the human factor. Say 5 5 shot groups with .0005 or less runout, same for .001, same for .003 etc. These would shot at 500 yards to see what effect the bullet hitting the throat would have on grouping and flyers. I thought that it had been proven that all bullets have a slight wobble in the first few yards

but like Damon, I bought a runout gage to find I did not need one. With good sizing dies case necks will be true
 
Would a FL Redding Sizer Die, do the "trick" for descent, Neck "runout" as, thier expander ball sits in a different position than, all the rest of,. the die manufacturers? Anyone using the Redding FL Die the one,.. w/o the Bushings?
 
Once upon a time I did statistically significant testing at 600 yards with "high" runout and "low" runout ammo. I was shooting master class scores with the M14 and there was a greater than 98% confidence level that there was no difference in scores based on run out so I have never measured it since. I did not make the decision based on opinion, mine or anyone else's opinion. There is no shortage of opinions but a shortage of meaningful test data.

If I had been shooting high master scores the answer might have been different. The answer may have been different for some other application. The only way to know is to do the testing.
 
I have always read and heard that .003" was the magic number. If you can keep runout below this figure you are good. I did some testing once upon a time and found it inconclusive. I had rounds that were zero, rounds that were under .003" and rounds that were under .006" but more than .003". I was unable to tell any difference group wise at 100 or 200 yards. This ammo and rifle combination was loaded so that the bullets touched the lands.
Tony Boyer, I would say, is up there pretty good as far as putting bullets in the same hole. In his book he briefly mentions bullet runout and talks about the first time he ever saw a runout gauge. Boyer was at a shoot or a show somewhere and some cat had gauges he was selling. He went on to write something like all his rounds were tested to show .007-.008" and he "decided right then and there that he didn't need the gadget to check bullet runout". All that said, in his book he talks about seating bullets to jam. A fact that dkhunt14 mentioned should be considered earlier in this thread.
The general impression you get when reading Mr. Boyer's book is that bullet runout is not something he worries about much and he writes about even less.....I am not saying totally dismiss runout...but it sure reads like Boyer did and no one can argue that the cat can shoot.
The best thing or method I have found for "fixing" bullet runout is L.E. Wilson straight line seaters. This is of course as long as the resize operation is not imparting runout into the case neck/mouth. Also, I thought it was Bonanza or Forester dies that have the expander in a different location....isn't it up high in the resize die so the case neck is going over the expander immediately after it is withdrawn from the neck resize portion of the die??? Others are way down near the decapping pin.
 
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Would a FL Redding Sizer Die, do the "trick" for descent, Neck "runout" as, thier expander ball sits in a different position than, all the rest of,. the die manufacturers? Anyone using the Redding FL Die the one,.. w/o the Bushings?

I have always found that a good and cheap way to reduce case neck run-out greatly is to size your case and bump your shoulder back with a Redding body die and size the neck with a Lee collet die. Works really good.
 
Would cartridges like the 6.5 Creedmoor with a substantial portion of the bullet protruding from the case neck tend to create more run out control problems?
 
Are there ANY,.. "fixes" for .005-.010 bullet "runout" issues ??? Would, a Lee Collet, crimp Die,.. HELP, this ???
Do I need to throw my RCBS Dies,.. in the Trash and BUY Redding Type "S" collett Dies ?? HELP !!!

One of the biggest causes of neck runout is if the expander is locked down off center.

I installed Forster high mounted floating expander and spindle assemblies on all my older RCBS dies to greatly reduce neck runout.

Below on the left a RCBS expander raised as high as it will move, and on the right the replacement Forster expander.

5kfnKwd.jpg



Below I installed a modified Forster expander and spindle assembly on my Redding .243 sizing die. I had to cut and shorten the threaded section of the spindle and locktite it in place. A rubber o-ring was installed under the lock ring to allow the expander to float.

kWbieba.jpg


The Forster high mounted floating expander enters the case neck when the case neck is held and centered in the neck of the die. And can not pull the case neck off center and do not need to size the case twice like using a expander die or collet die.

Y7Iyv8o.jpg



Another method is to remove the sizing dies expander and expand the case neck with a expander die. And expand the case neck on the upstroke of the ram with the case resting on its base. Cases fired in semi-autos can suffer damaged rims that can cause the case to tilt in the shell holder on the down stroke of the ram with normal dies.

sinclairexpander350.jpg
 
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