flyers / you ever get these ?

[willyp]

I may have mad a discovery goofing around in my loading area !
Have you ever loaded up a batch of your cases be they neck sized of FLS and have 4,5 or may 6 in a good tight group !  Then all of a sudden ZINGO there goes 1 or 2 like high or to the right or left of the group ?
I stumbled onto something the other day and i still have to try and prove my theory ?
I use the Lee case trimmer tools.  So i have the the shell holder that i clamp into my drill and use it to spin my cases to trim them.  Most of the time i pay no attention to what i am doing and just trim them and then  remove the burs .
I had a 15 cases i had shot from my 30-06 last  season the Friday before Buck season.  I save my targets all the time to just look at  and see how i have done on said day ! It was cold that day and a little windy. I was not dressed for the coldness and was not into shooting and the targets were bad but i din't care i just wanted to go get warm ? The grouping was acceptable for hunting because i seldom see a buck any more unless it is in high gear running across a far ridge !
The cases were not shiny  so i decided to clamp them into my drill and polish them up with some steel wool ? These were neck sized and  primers were out .
The first few were done and spun around just like a well balanced top ! Then came one that wobbled like a flat tire at 60 miles and hour ? Did a couple more nice spinners and then a couple more wobbles  .
No wonder i had flyers ! The cases were sort of crooked  ? This made the bullets come out  at different angles into the barrel !
If you this Lee thing try this and see if i am on to something ?
PS - I had loaded some range brass into my hunting ammo so these were not from my rifle ! i do keep track of my own once fired brass by marking it with a magic marker . I mark them with a number and where they hit on my targets ?
Let me hear what you think .

[Deleted]

It's called bullet runout. I roll my loaded cartridges on a flat surface to check for it. A sheet of glass is ideal. Any wobble will cause fliers. You can get a Concentricity gauge to check it too.

[willyp]

YEP ! That's what it is called .
I just figured that some folks whom aren't into reloading as deeply as lots of others could use this simple tip .

[davet]

Absolutely!! I load my 6.5 x 55 Swede cartridge for long range shooting from my Savage action\Shilen barreled rifle. Case prep is key to consistent long range shooting. I will segregate loaded cases by bullet runout. Anything with zero runout, then up to +-.002, and last, anything .003 or more. The .003 group are practice....the .002 group are "last to shoot in a match, and of course, zero runout is first.

I've shot all from a bench at 300 yards, and those with a .003 runout will be under an inch. But those with zero will be one ragged hole at 300 yards.