Run-out; Neck turning

[bigchast1]

fairly new to hand laoding for extreme accuracy What the heck is bullet run out. and does it effect accuracy.  Is neck turning worth the time and more importantly the 2-4 boxes of bullets it will cost me?  How much will it help a factory 700 in 22-250.  It now shoots .250'' at 100 yds center to center. Thanks for the lesson and give me a differnt load to play with for more experince with all these different components.

[Jose Grande]

Run-out is whether or not the bullet is perfectly straight in it's case.Neck turning usually helps accuracy. Seating a bullet half-way,lowering the ram & turning the case 1/2 turn,then finish seating the bullet  will help keep bullets straight.
As to how much help~~~~nobody can say for sure.It might not help at all. It may help a little. A .250 size group is mighty small.
The group size at 200 & 300 yd. is more likely to show effect from these things.
I shot a 3 shot group at 100yd. a while back you could cover with a 50 cent piece. I was shooting off-hand, a 45-70 Sharps,with Goex 2ff BP & a 405 gr. bullet.
This rifle opens up to nearly 3 in. at 300yd. on crossed sticks.


Keep me posted on your endeavors with the 22-250.

[Bob_K]

Runout is a measure of ammunition concentricity.  Theory is that concentric ammo in a concentrically cut chamber will perform more accurately than ammo and chambers that are not concentric.  When I was shooting service rifle LEG matches, I would measure the runout of the ammo that was issued to us and separate it into batches. The most runout batch was used at 200 yards off hand. The next worst runout group was used at 200 yards sitting. (Other factors have a greater impact in accuracy at 200 yards than ammo concentricity.)  The best batch was used at 300 yards rapidfire.  (There is no way to specifically orient ammunition in the chamber when it is loaded automatically from the magazine.)  The second best runout was used at 600 yards, orienting the highside against the same locking lug for all rounds.  Runout on the issue ammo was thought to be because of a thicker neck at that part of the brass.  Thinning case necks removes this high area, and when coupled with coaxial seating dies, produces some minimum runout ammunition.  Whether this will make a difference in a rifle/ammo combination that is already shooting .250 is up to you to decide.  Is your goal .125 groups?  Then ammo concentricity may be a part of all the things you do to get there.

[coopershooter]

lol! just kidding. you sound like you have a high class problem. are you shooting in the field or target shooting? i load several diffrent cartriges, but i only neck turn a few. for field shooting i dont think it would be worth the trouble.
 bobby olson

[K2]

Only you can say what it might be worth to you, for me it would be a waist of time and effort at 1/4 inch group size.  Are you going to be shooting ants at 100 yards?  If so it might matter.

fairly new to hand laoding for extreme accuracy What the heck is bullet run out. and does it effect accuracy.  Is neck turning worth the time and more importantly the 2-4 boxes of bullets it will cost me?  How much will it help a factory 700 in 22-250.  It now shoots .250'' at 100 yds center to center. Thanks for the lesson and give me a differnt load to play with for more experince with all these different components.

[Willyp]

I am not trying to be a wise guy,but how many .250 groups did you shoot,in a row?How many shots for group?[3 or 5?] This all comes into account.
I started neck turning,a few years back. It does help,some what, in factory rifles ,but is boring to do. What is done is simply truing the neck thickness.This will help to seat the bullet straighter and [IMO] cause a more even grip and relase,also.
However,you can over do it and make the necks to thin. The cases must be new and FLS. Then start with,5 or so,to set up the turner,to see what your cases tell you!
Before i start,I fls,trim and weigh the new cases,into two or three,weight groups. The heavist are[ mostly times] the thickest. I don't do anymore than true up each group and keep these all seperated.they will shoot different?
This is just my thoughts,on the matter,but it works for me.
A wise man one said aaa,darn,I forgot what he said!!!!!!!!
 :oops:

[longwinters]

John Barsness wrote an article on it.  If you look up "Factors In Accuracy, Part II" you will be able to find his article.  

LOng

[jeff]

The general reasons for neck turning have been stated and don't need to be repeated in this thread.  

However, the benefiits that are derived by neck turning for rifles that are factory chambered are overstated.  It would be a rare factory rifle that came with a neck tight enough to warrant neck turning.  Additionally, the cartridge head spaces on the shoulder and that is what centers the neck & bullet in the chamber.  Of course, we haven't asked whether or not the chamber is centered with the bore have we?  

I seriously doubt that neck turning provides any measurable benefit in any factory built rifle.  At best, I would rate it as an dream that might provide some extra confidence to improve their marksmanship skills.

[cal sibley]

I turned my necks for several years but never found it did much good for factory chambers.  If your .22-250 is producing 1/4" groups you'll not likely to improve it to any degree.  If I'm having concentricity problems I
switch to Wilson NS, bushing knockout dies.  They are excellent for producing concentric reloads.  Best wishes.

Cal - Montreal