Bullet run out

[olddav]

Bullet run out

I have been on this forum almost daily for the past six years and have learned a lot although still need more info about everything. Recently I have been looking into detecting and correcting bullet runout, but being the cheep person I am I did not want to spend too much money on tools. Saw where some members here had built their own concentricity gauge and became inspired.

I built a crude tool (ripped off the design) and started checking some of my reloads. I indexed each cartridge (at the high spot) and grouped them according to readings I got (3°,6°,8° etc...). I was encouraged by the results of my very limited testing at the range today. *My best 3 shot group with my 338-06 was 1/2" @ 100yards, those three bullets measured a 3° run out. If I *introduced a bullet that had a significantly larger number it impacted the target far from the other two. Prior efforts with the same load netted groups in the area of 1.25".*

So now I'm looking at ways to correct run out (how to build a tool). Who has a design they are willing to share?*

Until I have a tool in my hands I guess that I will just continue to index, categorize and shoot.

edit:
oops!
3°=.003
6°=.006
8°=.008

[foxx]

I use the Hornady tool for measuring/checking for runout. It has the ability to push the bullet over with a lever so as to correct the runout. However, I have also read that doing so is not as good as it sounds. Apparently doing so makes matters worse (or at least, not better) because you damage the seal of the bullet in the neck (or something like that) and therefore negate whatever advantage you created by reducing the runout. I don't know if that is true because I have never tested my own work. I just decided it might be true and therefore just use it to confirm that I DON"T have a runout problem. So far, I have had good luck using good brass (Lapua) and Lee Collet Neck Sizer dies (when able), and shoulder bumbing when necessary. I also anneal every 3 times.

So, I guess I am saying use your gage/tool to check, but don't bother trying to correct runout by bending or pressing a completed cartridge. Find a solution before you get to that point. Use your gage for sorting and confirming.

[Robinhood]

I am assuming you are talking about .003" when you put 3 degrees. Not a lot. You can try to correct run out 2 ways. Before seating your bullet or after. There is no scenario of removing run out, after the bullet is seated that I can see the benefit. The best way in my opinion is to us a die that does not over neck size the case.

[olddav]

I am assuming you are talking about .003" when you put 3 degrees.

Yep that's what I wanted to say, but failed!

[hafejd30]

I use lee collet die as well. Keeps runout under .002 for roughly 85-90% of the rounds. Worst might be .004 otherwise all usually under .003. Measured with Holland gauge

[FW Conch]

I also use Lee Collet Dies. With almost all of My reloading, I start out with the simplest things first. On the subject of runout, I seat the bullet about 1/16" at a time, rotating the case as I go. Doesn't cost anything, just takes more time. Give it a try. :-)

[yobuck]

Seating the bullet in several stages, and rotating as you go is a good idea with any die.
Certainly runout can cause a shift in bullet location.
Try marking the case at the high point with a sharpie, then feed each round in the chamber with the mark in the same place, say 12 oclock.

[m12lrs]

I use the Forster Case & Cartridge inspector. It allows me to check uniformity of brass thickness in the neck, runout after sizing and runout after bullet seating. It is nice to know where in the loading process runout is being induced.

I also have the hornady Lock-N-Load Ammunition Concentricity Tool.

I like my forsters better. Tried using the hornady for correcting runout. If it is just a tiny bit it works but if the runout is .005 or 6 my though is you mess up the neck tension moving it.

I have found if you sort your loaded ammo .003 or less is good for high accuracy work. Anything over .003 is for just shooting.

I have all sorts of bullet seaters. Micrometer seaters by forsters and redding that produce quality ammo but my favorite by far is the Wilson. Of course you need an arbor press but it turns out the straightest ammo for me. I seated 50 bullets with the Wilson the other night and I had 3 over .003. Most were around .001. I even felt the bad ones when I seated the bullets. Brand new lapua brass. If fire forming doesn't straighten them out I will cull those three.

[olddav]

Interesting info!

So it appears that if I am unwilling or unable to purchase additional hardware I am left with identifying, indexing and matching bullets according to runout. I guess I will start recording the group size and deviation from POA in regard to runout. If nothing else additional info will be provided and hopefully will lead to useful knowledge.

[m12lrs]

Interesting info!

So it appears that if I am unwilling or unable to purchase additional hardware I am left with identifying, indexing and matching bullets according to runout. I guess I will start recording the group size and deviation from POA in regard to runout. If nothing else additional info will be provided and hopefully will lead to useful knowledge.

Doesn't really matter what Hardware you use sorting above.and.below 0.003 is about.all you can do.

Measuring runout is very simple. If your device measures it accurately and consistently it's all you need. Now reducing it during your reloading steps is where the challenge is

You can start by measuring runout on your sized brass. If it has runout.at.that stage I would be curious to see if it.gets better or.worse with bullet seating.

[hafejd30]

I also use a Redding seater and seat halfway, turn, then seat fully

[olddav]

I checked all my sized brass both new and fired, 95% measured between 000-.006 and the majority falling in the .002-.004 range. I marked each case so that when I load them I will have some point of reference while measuring runout on the final product.

I have been rotating the brass while seating the bullet (rotating 180°), I think that I will try rotating them one revolution at 90° increments, can't hurt.

[J.Baker]

I've found that it really doesn't pay to be overly concerned about bullet run-out unless you're shooting VLD-type bullets that have minimal bearing surface. Shorter/common for caliber bullets (i.e. 50-55gr .224cal bullets) that have a longer bearing surface seem to be less affected by run-out, whereas run-out is much more critical with the VLD-types due to the limited amount of surface area (in relation to overall bullet length) that's in contact with the rifling.

In my experience neck tension and it's uniformity will have more overall effect on accuracy than bullet run-out which equates to annealing and neck turning or reaming.

[m12lrs]

I've found that it really doesn't pay to be overly concerned about bullet run-out unless you're shooting VLD-type bullets that have minimal bearing surface. Shorter/common for caliber bullets (i.e. 50-55gr .224cal bullets) that have a longer bearing surface seem to be less affected by run-out, whereas run-out is much more critical with the VLD-types due to the limited amount of surface area (in relation to overall bullet length) that's in contact with the rifling.

In my experience neck tension and it's uniformity will have more overall effect on accuracy than bullet run-out which equates to annealing and neck turning or reaming.

That is probably why Walt Berger designed the VLD to be jammed into the lands 1 to 2 thousands. That way with no jump and the bullet lined up in the rifling runout problems are greatly reduced.

[SidecarFlip]

I use the Hornady tool for measuring/checking for runout. It has the ability to push the bullet over with a lever so as to correct the runout. However, I have also read that doing so is not as good as it sounds. Apparently doing so makes matters worse (or at least, not better) because you damage the seal of the bullet in the neck (or something like that) and therefore negate whatever advantage you created by reducing the runout. I don't know if that is true because I have never tested my own work. I just decided it might be true and therefore just use it to confirm that I DON"T have a runout problem. So far, I have had good luck using good brass (Lapua) and Lee Collet Neck Sizer dies (when able), and shoulder bumbing when necessary. I also anneal every 3 times.

So, I guess I am saying use your gage/tool to check, but don't bother trying to correct runout by bending or pressing a completed cartridge. Find a solution before you get to that point. Use your gage for sorting and confirming.

I use and have used one for quite some time for all my medium to long range hand loads and I've experienced no issues at all. One way to achieve concentricity is seat in stages and rotate the cartridge and partially seated pill in the shell holder.

Typically, seating Berger VLD Hunters in Lapua brass with an RCBS Gold Medal Micrometer seater and seating in stages, I can get my TIR within 0.002 and a slight bump with the Hornady lever gets them dead nutz.

The straighter they enter the lands, the better they fly.

[olddav]

Bullet runout is introduced during bullet seating. I've tried rotating the case as the bullet is seated but it hasn't produced consistent results. So, I am goning to index the each cartridge at the high spot, note the runout on the side (via sharpe), group the cartridges according to their runout and make lots of notes. Should be interesting!

[SidecarFlip]

Get yourself a Hornady run out Gage. Much easier. I use it and a Sinclair comparator. Just ran some 300 win mags a little while ago for a customer. I chron'd them at 3200fps with 82 grains in Nosler cases with Federal LRM primers. Gonna back them down 1/2 grain. Close about 3000 fps is plenty for elk or anything else on 4 legs. 185 Berger VLD Hunting bullets. Did I say they are tack drivers? Sub sub MOA at 250 in his stick (custom built Pierce Precision Titanium action (700 clone) with a Shilen tube and muscle brake, wearing a MacMillan CF stock and a Swaeovski scope.

TIR on the case mouths after turning was 0.001 and TIR on the seated pills was 0.000-0.002 depending. 0.002 is acceptable. I use RCBS Gold Medal Micrometer seater dies exclusively and I rotate the case as I insert the pill...always. Always use bushing dies, usually John Whidden (in this case John built the die just for this chamber). Expensive, certainly, shooting lights out ain't cheap.

He's happy, I'm happy. he's got elk fever.

[foxx]

I just started selling eggs to Chinese immigrants from Cuba...

[olddav]

I just started selling eggs to Chinese immigrants from Cuba...

I'm sure you saw this coming, What?

[yobuck]

I just started selling eggs to Chinese immigrants from Cuba...

Are they match quality eggs or just regular eggs?

[foxx]

Match. They aren't cheap, though.

[SidecarFlip]

I just started selling eggs to Chinese immigrants from Cuba...

I would assume you suck eggs....??

[The Old Coach]

Gee whiz, what are you using for seating dies? I took a flyer at measuring runout years ago, and even with ordinary RCBS seating dies I never saw more than about .002". I quit bothering with it.

[Iowa Fox]

I like using a runout gage to check my process while setting up, especially new dies. Once I get things fine tuned I don't use it. I have found some full length sizing dies where the expander ball is a horrible culprit for pulling necks crooked. Seating dies are also an offender when it comes to runout. The best thing is to keep good written notes in a notebook.

[SidecarFlip]

One issue with sizing dies is the expander ball is off center and it pulls the necks out of concentric alignment with the case when sizing. Whidden overcomes the alignment issue by adding an 'O' ring between the stem fixing hut and the die body. That allows the stem to float and it's an easy addition to any die, I employ the 'O' ting on all my dies now no matter what brand. Additionally, John used 2 'O' rings on his bushing dies, one on the stem and one on top of the bushing locating nut. Everything is able to self align that way. Neat idea and easy to copy with suitable sized 'O' rings.

Before I used Whidden dies, I spent considerable time fiddling with expander ball stems getting them concentric with the die body (RCBS) is especially bad, but adding the 'O' tings and allowing the stem to float eliminates the side thrust and neck deflection. Lots easier that way.

When I shot a group on any load workup, I never consider the first shot as viable. Same thing when you go hunting, you send the first one to 'foul' the tube and then hunt, ot you foul the tube at home before you hunt.

I've also found that the larger the charge the tighter the groups get (all other aspects being right). I like talking them up to where I start to get heavy bolt lift and back off 1/2 grain or so. I don't recommend that for the faint at heart however. In fact I don't recommend it at all. What works for me may blow up in your face.