Runout??

Tiny

The vast majority of Benchrest shooters have a seating die that is about as good as it gets.
However, I have found that as good as they are, they can only make straight rounds if the case that went in is straight. So, in my opinion, based on my own observations, the biggest culprit is lin the sizing operation..........jackie
 
tiny68 said:
Ok, Rookie question. It runout influenced more by the size (FL or neck) or the seater?

tiny
Click to expand...

Seater die!

80 percent of all seater dies induce significant runnout because they do not support the neck while seating the bullet.

The best/only seater dies that produce little to no runnout are seater dies that are cut using the chamber reamer of the same barrel.

Tight minimul FL sizer die fit to chamber + tight seater die made from chamber reamer= minimal to no runnout.

My PPC loaded round runnout= less than .0003"...........Don
 
Don

A typical sized case, say for a .262 neck, will be sized, at the neck, down to .257. That is .005 clearance in your seater made with your chamber reamer.
Even after the bullet is seated, you still have what ever clearance your loaded round has in your chamber, probably about .0013.
Since that neck has so much clearance in the beginning, I don't quite follow your logic.
I would think that a die with a body that fits the case body almost at "zero" after full length sizing would be the best approach.
But, if you are getting that good of a runnout reading, what you are doing is obviously working.......jackie
 
Redding reloading dies..

I just read the response that Redding die company has to this same question...They do NOT believe that the sizer die induces runout..
Go to their website and check out the technical help section..lots of info about this topic...
 
eww

I certainly would not wish to contradict Redding, they are a well established company. (I use their products).
But here is what I can tell you. I have a Redding 6PPC Competition Neck Sizer-decapper. When I use it to neck size a case, (.265 bushing), after using a Redding body die to hit the shoulder and the body, my loaded rounds will typically run out about .003.
When I use my solid die, (no bushing), with the same neck diameter as the .265 bushing in the redding die, the cases will typically run out .001 or less......jackie
 
dies

I know custom dies rule in BR. But, how good is the Redding Competition bushing style seater dies? I have been truely impressed with the results from my 223, 22-250, 22-250 AI, and 6 AI. However, I wasn't trying for BR accuracy. I guess I'll find out. I have a set on order from Bruno's. I may be the only one at the match not using Arbor style seaters.

Thanks for your thoughts, tiny
 
jackie schmidt said:
A typical sized case, say for a .262 neck, will be sized, at the neck, down to .257. That is .005 clearance in your seater made with your chamber reamer.
Even after the bullet is seated, you still have what ever clearance your loaded round has in your chamber, probably about .0013.
Since that neck has so much clearance in the beginning, I don't quite follow your logic.
I would think that a die with a body that fits the case body almost at "zero" after full length sizing would be the best approach.
But, if you are getting that good of a runnout reading, what you are doing is obviously working.......jackie
Click to expand...

Not if the sizing die sizes only 3/4 of the neck length, that leaves 1/4 of the neck unsized and having exactly the same fit as the gun chamber since both were produced using the same reamer, cant get any closer fit than that...............................Don
 
While at the Super Shoot a few years ago (2004 or 2005) Scotty Crawford had a gadget that was absolutely perfect for measuring loaded round runout. I measured rounds loaded with four different brands of seaters, and without question Don's seater delivered the straightest round. Neil Jones was second (around .001). I won't mention the other two brand names, but they were in the .005-.006 range.
 
I agree with Jackie that a one piece FL die or very close NK die will
produce the straightest case.It does need to be very close to the chamber
or the case can lay in the bottom of the chamber. Bushings are rarely
true and machineing a cavity in both ends of a die can be a problem.
I do believe Don is correct about seaters, when the lower part
of the neck is unsized and the base of the case fits the seater well
you have an optimum setup. I also believe that those who seat
at jam and beyond negate the errors in seating, for better and worse.
 
No doubt this is true. Cases that don't load straight will do it over and
over. Anneal them properly and they will load much straighter for a
short time. Find a good case and try loading it with dies that don't
match well and it will be out As in bullet making, there should be a
fine relationship between core seater and point die
 
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