Run out

[ArtinNC]

On the bullet of a loaded round how much run out is to much ?

 

[RustyInBend]

I strive to be less than 2/1000 on the neck, and am ecstatic to be sub 1/1000 ... measured on my always helpful Sinclair Concentricity Gauge.

 

[JFrank]

Depending on the chamber job but there should only be a few thou clearance in the throat so bullet can be off quite a bit and still be corrected when chambering the round.
Yrmv of course.

 

[Bill Norris]

^^^^^^^ This

 

[dusterdave173]

I bought a used Sinclair run out tester as pictured above
Used it for a month or so....I was happy that I never had anything over .003 and usually .002 was all I would see...
I keep it so if I get run out with a new load or cartridge I hope to be able to find out where the issue is but so far.......It has been a non issue and even the worst run out I saw did not show up on target at all...

 

[Doug Beach]

What JFrank said. On a lot of chambers, throat diameter is somewhere close to .0005” over bullet diameter. That’s five ten thousandths, not five thousandths.
Chambering the round will hold the bullet within that alignment range, whether your initial runout was zero, or .005”, or more.

 

[Murray Brook]

Chambering the round will hold the bullet within that alignment range, whether your initial runout was zero, or .005”, or more.

I have always felt the having a straight round in the first place is better than having the chamber straighten it out because I feel the neck tension ( which is important to accuracy) would change. I must say I have never tested this or read of such a test but it would seems right to me. What do you guys think about this.

 

[SeabeeKen]

I've checked runout twice in 10 yrs. I dont worry about it. All it did was show how well my dies did

 

[Doug Casner]

When 1 worked at lake city the run out was .005 on ball . Just chamber and boom. Doug

 

[209jones]

Runout tool is maybe handy to troubleshoot with at times, to figure out where an issue is occurring or not, IE; sizing or seating. Possibly for proving or disproving a good or bad die or technique. Not that often that it'll actually tell you any useful info though, more to satisfy curiosity than anything else.

 

[ronemus]

I used my Sinclair gage intensively when I was refining my reloading process, and still do when I make a change. Once the technique is established I run QC checks every once in a while. I can routinely get runout <0.0005" on the neck and <0.003" on the bullet nose.

 

[ArtinNC]

Guess I'm not to bad , I'm getting 0.003 on the bullet . But I'll work for better .

 

[L.Sherm]

I've seen as much as .007 shoot .250 moa at 700 yards. So take what you want from it. My personal opinion its why I dont like resistance chambering a round, just my theory.

 

[jackieschmidt]

Simple logic dictates that we should strive to produce loaded rounds with as little runout as possible.

However, through the years, many of us have run various test proving to ourselves that as long as it is within reason, (.002 to .003), it simply does not make any difference.

 

[L.Sherm]

Can't remember for sure but wasn't it Eric Cortina who made some rounds crooked on purpose and shot them and made no difference.
Don't remember by how much.

 

[L.Sherm]

I agree Jackie ev

Simple logic dictates that we should strive to produce loaded rounds with as little runout as possible.

However, through the years, many of us have run various test proving to ourselves that as long as it is within reason, (.002 to .003), it simply does not make any difference.
I agree Jackie we should strive for it but I read were guys just obsess over it, like always target is the determine factor

 

[Bill Norris]

Can't remember for sure but wasn't it Eric Cortina who made some rounds crooked on purpose and shot them and made no difference.
Don't remember by how much.

And F-class John did as well I believe up to .015 and saw no change.

 

[nksmfamjp]

I measure about 0.05” behind the tip or 0.02” behind the plastic insert. I have seen runout up to 0.17”. If I grouped that ammo greater than 0.013” and less that 0.007”, the difference was visible in the groups ….maybe 15 shots of eack.

 

[hoz53]

Depending on the chamber job but there should only be a few thou clearance in the throat so bullet can be off quite a bit and still be corrected when chambering the round.
Yrmv of course.

I believe in wat you say here south prarie - it has always seemed like common sense dictates we would get better accuracy if our bullets are into the lands some so the bore straitens them up with the chamber. i know that some of the best shooters to come down the pike have believed this and done it this way. but what about people who get best accuracy by shooting an out of the lands seating depth?. this has me puzzled and i know they arent all FOS. I have experienced this myself and just scratched my head! Berger has their VLD seating depth test and they say many times a vld will shoot better out. good thing we have the target to give us the honest answer about what works best cause many times its difficult to figure out why things happen- weve known this a long time. still i want to know. trying to figure it out is what makes it all worth doing to me.
merrry xmas

 

[VA_XTC_Shooter]

Asking for some history here. Did the concentricity phase come before we saw so many super accurately/concentrically machined chambers?
I ask, wondering if more concentric rounds show an improvement over less concentric rounds in a looser chamber we see these days?
If that is the case, and chambering improved after, I could see the "old" work that showed improvement carrying on as an assumption until tested.

Or it's all just made up junk to sell gadgets from day one?