Run out

Tim Behle

Well-Known Member
Joined
Mar 16, 2002
Messages
367
Location
McNeal, AZ
How much bullet run out is too much?

I try to keep mine as low as possible. I separate those out that I can get down to .002" or under to be used for hunting, or when I want to record a group. But I end up with quite a few higher.

How high is too high? What do you do with those that don't meet your criteria? I just pulled five bullets that were out by .005"-.006" Then reseated them in the same cases. I got two of them down to .003" the others went to .004-.005"

Should I have dumped the powder and resized the brass again? Any suggestions?
 
Tim, If I had to guess, I'd say your using RCBS dies. They are notorious for being out of round. Most of the guys at the 1000yd range avoid them like the plague.

Assuming that is wrong, you may have a chamber that is "Banana'ed" It kinda had a curl to it. All of your fired rounds will pick up the chamber shape to some extent. Some might be the same orientation (rotation)as last firing and now their worse, others might be opposite that and now they get better.

Spend some time checking the brass before you resize, and after. Move your indicator to the center of the case body and support the case on the mouth and head at the same time. Now check. Keep in mind, double the result when you check the bullet runout because it's outside the supports instead of inside. Your .006 runout on the bullet means its really .003 off center.

Hmmm, now to really answer the question, is .006 bad. For ME, yes, on my match gun. Would I be afraid to shoot at a woodchuck at 400yds with a 22cal and ammo that measured that, No. Would I be surprised if I missed, (with a good range) Yes.

Most of all, Don't think that it's You. There's nothing you are doing to cause that amount of essentricity. Your gun or your dies are hosing you. For <$25 you can find out if it's the dies. Get a Redding FL die and see if it fixes it.

Be happy with .001 or .002 on the bullets. You'll grow old trying to get much better than that.
 
I'm happy with just .002" or less, and I'll use .003", but what do I do with the ones I can't get down that low? I have been using the RCBS FL dies, but the Redding dies should be here by the end of the week. Will it be able to straighten out those cases that are out?

I don't think the problem is with the chamber, if it were, I'd have problems with all of the brass. Not just 3-4 out of every 20 I load.
 
Troubleshoot your problem by doing run-out on your case neck after sizing then again after bullet seating to isolate which step is causing the runout. I have found runout can be caused by seating dies also...

Nodak
 
The only die set I've never gotten great runnout from is a REDDING. Maybe it's a lemon but ALL DIES WITH EXPANDER SPINDLES NEED TUNING. Think about it--what are the odds the expander ball is sitting in the middle of the die when the screw that holds it is far away. NIL!! Heres what to do to TUNE YOUR DIE.
Turn your spindle out so the decapping pin is a ways outside the die body (Not so far that the expander ball hits the bottom of the case.).
Size 5 brass and check runnout. If not good turn the expander spindle 1/8 turn up into the die. Size 5 more--check runnout if not satisfactory turn the spindle 1/8 more turn.
Keep repeating this until you find the "sweetspot". I guarantee you WILL IMPROVE YOUR RUNNOUT SIGNIFICANTLY. I'm not sure the spindle has to be exactly in the center of the die to make great runnout BUT it has to be close. IF THIS DOESN'T MAKE SENSE LET ME KNOW AND I'LL EXPLAIN IT BETTER.
If this doesn't work I owe you a beer--if it does you owe me a beer (like either of us will ever collect eh??!!) I have to admit hat I am no longer a rcbs die lover. If I'm cheap I go hornady--if I love the gun/caliber it's foresters. I have been able to get hornady dies to make AS GOOD of ammo as my Foresters by fiddling with the seating stem.
With cheap dies and rem/win factory brass you should be able to get 1/3 of your loaded ammo under .0015".....1/3 under .003" and probably never any over .0045". Sort your ammo into groups and mark the best with a green sharpie marker on the primer--use these for long range matches or hunting. Mark the bad stuff (which will probably shoot right with the best stuff in a huntingrifle) with a black marker and usethese for testing/fouling whatever. And the stuff in the middle becomes backup ammo in case you use of the green marked stuff.
 
First determine if it the rifle or dies. Run your fired brass thru your tool and check it-mark the high spot,if any. Then resize, and check it again.There are several ways to tune your dies. The method kraky mentioned is one of them. I use whatever it takes, to include putting a #57 O ring around the die below the lock ring, letting the die "float" in the threads. Another method is to polish(notice I didn't say grind) the expander ball with 600-800 grit wet or dry sandpaper, then flitz metal polish. Then set the decapping stem where you want it, and loosen the lock nut on top of the die, resize a case, but stop with the ram in the upstroke, with the expander ball inside the neck. Tighten the decapping rod --this should center the decapping ball. Use plenty of lube and take your time setting up the die. If its still out after all this--buy new dies.
shocked.gif
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I have had Out of round Redding dies, but this is not the norm. I have about switched over completely to Redding.

[ 02-04-2003: Message edited by: Chris Jamison ]
 
Tim,

Max here has the best solution for you. The Lee Collet dies eliminate the expander altogether. To be honest, it's been about 2 years since I used a die I didn't make so I didn't really think to say anything about the lee dies. There is actually the most used commercially made die at the PA 1000 yd club. I made my own collet dies and was not real thrilled with the longevity of my brass but then they were my first attempt at making collet dies. I made mine from 416SS, collet and all.

Another thing I do is turn my necks on all my guns cases. I use two different methods for that also. My match gun's cases are all done in a CNC lathe. My hunting guns are done with a Sinclair or K&M Turning tool. I like the K&M Tool better but I have every mandrel for the Sinclar one so I use that one on the smaller cal guns. You can turn your necks down so that your die will close the opening just enough to get the bullet press fit you want. I go to about .0025 under. Now you may throw away the expander and don't need to worry about pulling on the necks of your cases. For instance, I use a 7mm expander for all my 30Cal cases. All I want to do is knock out the primer. Don't let that sucker touch anything.

Several companys sell carbide expander buttons for thier dies and you can get one of them also. They're about $20 if I remember right. I kinda prefer turning the necks and letting the die do its thing so I never bought one. Actually, I did ask one of the vendors at the range to bring me one, Then I asked again, and again, and after the 7th week I said screw it. I try to buy from the guys at the range but I'm just gonna go so far out of my way to give someone money.

The idea of "tuning" sounds pretty reasonable. I'm not going to try it as I don't have the problem any more but it sounds plausable that it would help.

For what it's worth, My swift dies are Lee Collet dies and just because my brother got a set of horrible out of round rcbs dies we decided to do a test. We chucked up the dies in the lathe and indicated the opening, then the neck area. The Lee dies were dead nuts on the money.

Let us know what helps You the most.

It is kinda funny, almost every time someone has a problem, My solution is to go buy something. I'm laughing as I type this but that's the general cure at the 1000yd club!
 
Hey Tim,

I was looking back at my first post and just for the record, what kind of dies DO you have??????
 
To improve concentricity of loaded ammo:


1) Get rid of any expander balls

2) Get a die that uses neck bushings so you can control neck tension.

3) Turn your necks, if your necks do not have consistent wall thickness, they will not load concentric.

4) Measure wall thickness variance, once again if the wall thickness is off, once you shoot or size, the brass will not be concentric across its length. Cull the brass with large wall thickness variance.
wink.gif
 
I've loved the Lee Collet dies since I first ran across them several years ago. But for what ever reason, I never did buy any for this rifle. I did buy a set of RCBS neck size dies. Big mistake. I've never seen dies give me worse run out.

Right now, I'm using the RCBS FL dies and Competition seater. I partially resize until the brass gets hard to chamber, then bump the shoulder back with the same FL die.

I did order the Redding bushing die and a .310 bushing the other night. I've been meaning to get one for better than a year, but for some reason I keep putting this rifle on the back burner.
rolleyes.gif
 
Jim Carstensen who advertises in Precision shooting and on the BR central board can convert regular dies to bushing and non expanding ball for $35. He does good work and quick turn around. He has converted several of my older Forster Bonanza BR dies to bushings. Price does not include the bushing. Lot of BR shooters use him for that work and he can make custom FL sizing die off your chamber reamer. He makes an undersized insert that is squeezed into the die blank. If you just ream a blank die with a chamber reamer you have no FL sizing! Resize reamers are undersize compared to the chamber reamer.

Good Luck

BH
 
BH,

I'm going to have Jim modify my other Redding FL dies for bushings too.

I wonder how he does such an undersized insert with the chamber reamer, any idea? What does he charge for this service? Does this run all the way to the neck or just the bottom of the shoulder?
 
Tim,

I did buy a set of RCBS neck size dies. Big mistake. I've never seen dies give me worse run out.

What was the runout "before" you neck sized?
The neck sizer will not hold the body tight like the FL die will, so consequently it will not correct any runout that already exists. Your FL die should, with out an expander produce near "perfect" cases and correct any runout problems in your brass from a bad chamber.

My 300 Ultra chambers neck area is eccentric in the order of + .005" at the 2 o'clock position so all I can do is FL size or index the cartridges to gain some consistancy. I mark the casehead at 3 O'clock and index the neck sized cases right now. I'm getting less than .005" runout way up on the bullets nose like this. I've not done a chamber cast to see if the neck or the body is lined up with the bore yet but one of them isn't.

With the Redding dies, which I still prefer, I've noticed the decapping stem will orbit the center and "never" be centered. If you leave the lock nut loose on top it will pull it closer to center as you draw the case neck back over the expander, but it isn't perfect. Redding dropped the ball with keeping their seating stems concentric. They are so far off it simply makes it impossible. Example, I use an RCBS Casemaster to check runout. if you take the seating stem out of the die, remove the decapping pin and collar, lay it in the supports, one one each end of the rod itself with the pin end to the left up against the stop and indicate off the flat just beneath the knurled head. There is always about .010" - .015" runout on the threaded adjustment head and it's only 1.0" in length at that point too. You can double that runout figure because the rod length is about that on the longer cases down to the expander ball. The rod is pressed in a bore that is not paralell for some reason or another, the threaded part is fine it's just the bore that holds the stem that is way off. If the threads on the adjuster are loose enough (lockring left loose), the expander will pull over close to center when with drawing the case but that's as good as it gets. The only way you can tune a stem to center up is to hope that the threads are unparalell also, causing the orbiting expander to intersect the bore centerline at some point. This is highly unlikely considering the threads always seem on center perfectly.

The carbide expanders are ball shaped almost and float on the stem with the hole in them larger than the stem itself, that coupled with leaving the lockring loose is the best way I've found to use the expander "if you must". I usually only use them to iron out dented necks if needed, I try to avoid using them. The smaller surface area on the carbide as well as it being harder usually doen't require lube, but if necks get harder or need to be opened up too much cause you die squeezes them down too far you'll still want lube, pressure to draw over the ball will tell you. I have had to use the ball on my Ultra with my neck bushing die because my bushing is too small now by about .003" which would leave me .006" tension and it takes some effort without lube but has not pulled necks up enough to cause tight headspace yet (3 times) using no lube. I get less than .001" runout using my FL dies.
 
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