Concentricity or lack of. Can you calculate flyers at distance

[Canuckienns]

I know that excessive run out and poor concentricity will cause flyers. Is there any way to determine how much runout relates to flyers at long distance shooting. Bench rest 600 to 1000 yards.

 

[gpoldblue]

I know that excessive run out and poor concentricity will cause flyers. Is there any way to determine how much runout relates to flyers at long distance shooting. Bench rest 600 to 1000 yards.

I think you'll get more fliers due to case/neck runout,especially with no-turn necks and non-sorted brass, than you will of bullet runout........how much error is hard to say due to ambient conditons and shooter skill and quality of equipment. Remember,the bullet MUST enter the rifling straight....if it is askew for ANY reason,you are subject to a flier.

 

[Canuckienns]

The case neck run out is terrible with Hornady brass, even after full length resizing with a hornady case and neck die, and uniforming mandrel. 004 to 005 is the norm. With Starline I just received it is .002 to .025. much better.

 

[Coyotefurharvester]

If your cartridge case neck chamber clearance is 0.0025(chamber neck 0.005 larger than loaded neck dia) how can 0.004-.005 run out matter, chambering the rd will reduce it by about 1/2. Do you have a chamber with 0.010 neck dia clearance?

 

[Bill Norris]

If your cartridge case neck chamber clearance is 0.0025(chamber neck 0.005 larger than loaded neck dia) how can 0.004-.005 run out matter, chambering the rd will reduce it by about 1/2. Do you have a chamber with 0.010 neck dia clearance?

Agree, the chambered round can only have the amount of runout allowed by chamber dimensions.

 

[Canuckienns]

We are talking about a 6mm ARC Ar15. Obviously its a no turn chambering. I shoot 6 dasher in IBS and Freedom Benchrest and I have zero runout, and I win and place a lot of the times in big shoots. Just trying to get the 6 mm ARC to perform better.

 

[gpoldblue]

We are talking about a 6mm ARC Ar15. Obviously its a no turn chambering. I shoot 6 dasher in IBS and Freedom Benchrest and I have zero runout, and I win and place a lot of the times in big shoots. Just trying to get the 6 mm ARC to perform better.

I and several others do cleanup neckturns for our AR-15's and M1-A's....just turn the high spots off....
have had no negative effects.
Good luck and stay safe.

 

[chkunz]

I know that excessive run out and poor concentricity will cause flyers.

How do you know that?

I did a lot of research on this many years ago with an M14 shooting Master Class scores at 600 yards and it did not make any difference at a 98% statistical confidence level. After that I stopped being concerned about it and gave the concentricity gage away.

For bench rest or F Class it may be significant, but it takes a lot of data to say with a reasonable confidence level.

 

[Canuckienns]

I learned from all the experienced long range bench rest shooters, and hands on that concentricity was important.

 

[mikecr]

Is there any way to determine how much runout relates to flyers at long distance shooting.

Not in MOA or anything like that.
TIR exceeding a chamber clearance causes a chambered pressure point.
Enough pressure point force can affect early barrel vibrations.

You should never reach that with AR15 clearances.

 

[wwbrown]

Is your crystal ball clear??