How does seating method effect runout?

[rcol317]

I have seen a couple post recently that indicate the way a bullet is seated determines the concentricity of the bullet but did not explain what that method is. If you have experience or understanding of this fact please explain. Thanks

 

[ar10ar15man]

inline, supported well, case prepped well .
all things that help keep a bullet straight, and not go sideways.
i do not use a loading press to seat bullets.
inline dies (wilson) and a small arbor press

 

[alf]

It begins with straight brass........

 

[rcol317]

I am aware of the need to uniform necks, brass concentricity etc but I read it depends on how you seat the bullet. Not sure if they meant rotate brass as seating bullet, seat bullet one continuous push or what ever. I use wilson inline with press for my F class rounds and they seem to be straight but I also turn the necks before I load. Maybe no big deal. May just be a guys opinion. Don't see many of those on this site. Thanks

 

[Buzzsaw]

If you are not using an inline type seater, just a regular one, seat the bullet in small steps. seat a tiny bit, lower press arm, rotate the case a bit and repeat till fully seated.
This is an OLD trick that works.

 

[Jeffrey Van Zandt]

I have seen a couple post recently that indicate the way a bullet is seated determines the concentricity of the bullet but did not explain what that method is. If you have experience or understanding of this fact please explain. Thanks

https://www.accurateshooter.com/technical-articles/reloading/expander-mandrels-and-neck-tension/

 

[Jeffrey Van Zandt]

http://www.xxicsi.com/hydro-bullet-seater.html

 

[Wedgy]

Find out where the runout is induced, is your brass concentric after you size it ?
Or does the runout happen after you seat a bullet ?

 

[Rhovee]

You seat the bullet half way, then spin it 180 and seat it fully.

 

[Mikecr]

I wouldn't have guessed this and tested everything else. But it works:
- Seat bullet base-bearing junction, with a kiss of your seater, ~1/32- 1/16" deep
- Back off seater, spin the round 180 degrees, fully seat to desired (in one move)

Of course this is barring any other influence issues for straight seating.

 

[MagnumManiac]

I wouldn't have guessed this and tested everything else. But it works:
- Seat bullet base-bearing junction, with a kiss of your seater, ~1/32- 1/16" deep
- Back off seater, spin the round 180 degrees, fully seat to desired (in one move)

Of course this is barring any other influence issues for straight seating.

This is how I do it with hunting rounds, comp rounds are seated with competition type micrometer seating dies.
My brass starts out very straight before seating is done.

Cheers.

 

[bigedp51]

If you do not have a inline seating die like the Forster or Redding, a Lyman type "M" expander will help seat the bullets straighter and more concentric. The bullets can be hand placed before seating to insure the bullet starts straight into the case.

 

[Rudolph Ferdinand]

inline, supported well, case prepped well .
all things that help keep a bullet straight, and not go sideways.
i do not use a loading press to seat bullets.
inline dies (wilson) and a small arbor press

Here is a question about the arbor press, are they better than a standard reloading press? I have played with the idea of getting one and I have watched Youtube video from a guy from the UK using the arbor press.

 

[Rhovee]

It's not the press as much as it's the dies. I really like the Arbor press because I can seat bullets and reload at the range if necessary. Saves trips. Force gauge is nice and you can see what's going on.