Forster Ultra seater problem?

[JohnD]

Has anyone had a problem with their Forster Ultra seater producing excessive runout?
Is there a trick to setting these things up? I just loaded some rounds and the average runout is >.004 while the resized case was < .001.

Thanks for any suggestions. John

 

[kelbro]

Is your bullet tip bottoming out in the seater plug before it contacts the datum?

 

[CatShooter]

Is your bullet tip bottoming out in the seater plug before it contacts the datum?

What "Datum"??? ?

Bullets don't have Datum lines, they have ogives.

 

[kelbro]

Semantics. My seater plugs do not technically reach the ogive.

 

[CatShooter]

semantics

Not.

Technical terms have meanings - use the wrong terms and you pass on the wrong information. (not counting that you look kinda silly, too).

 

[jlow]

I would also like to see someone weight in on this with a good answer.

 

[kelbro]

semantics

Not.

Technical terms have meanings - use the wrong terms and you pass on the wrong information. (not counting that you look kinda silly, too).

I believe that the standard definition of the ogive (used here) is where the bullet measures the same as the bore diameter, correct?

And I believe that the definition of datum is any repeatable point that you choose to take a measurement. In this case, it would be the location where the ID of the bullet seater plug contacts the bullet, right? That point would vary between Forster, RCBS, and Redding seater plugs.


This is a common problem with VLD bullets and factory stock seater plugs.

 

[savageshooter86]

John do your cases have this runout before seating the bullets? Check the runout of your prepped brass and tell us what #s you are seeing

 

[CatShooter]

semantics

Not.

Technical terms have meanings - use the wrong terms and you pass on the wrong information. (not counting that you look kinda silly, too).

I believe that the standard definition of the ogive (used here) is where the bullet measures the same as the bore diameter, correct?

And I believe that the definition of datum is any repeatable point that you choose to take a measurement. In this case, it would be the location where the ID of the bullet seater plug contacts the bullet, right? That point would vary between Forster, RCBS, and Redding seater plugs.


This is a common problem with VLD bullets and factory stock seater plugs.

Neither are correct.

The ogive is the whole part of the bullet. from the point to the bore diameter. The seater cup pushes on the ogive, unless it is not properly shaped, and the nose of the bulet hits the back end of the seating cup.

The datum line is a standardized (and accepted) point to make measurements from, in this case, it is used for case shoulders - straight cases do not have datum lines.

It is not used in bullets, it is used for case shoulders.

 

[m500]

It is possible you have another situation going on. You may be starting to seat the bullet before the case is all the way up into the chamber sleeve. I have seen this possibility when loading 60 grain v max in 223. I was loading long for my throat and the case just barely got snug in the chamber before the bullet started to seat. Had I been loading them to 2.250 they would have started to seat before the case was being aligned in the chamber. This may not be your problem, but it is something you should check for considering your problems. Good luck.

 

[gotcha]

Now that we have terminology issues resolved I like M500's advise. Would also suggest removing seater stem & checking to see if bullet tip is bottoming in seater before contacting ogive. I've had this happen with die you're using. You can use a small drill to deepen the plug & allow for the longer bullet tip. Chamfering the plug so the bullet doesn't hang up on the rim there might also help. Hope I've got my terminology correct. There might be hell to pay

 

[kelbro]

Now that we have terminology issues resolved I like M500's advise. Would also suggest removing seater stem & checking to see if bullet tip is bottoming in seater before contacting ogive. I've had this happen with die you're using. You can use a small drill to deepen the plug & allow for the longer bullet tip. Chamfering the plug so the bullet doesn't hang up on the rim there might also help. Hope I've got my terminology correct. There might be hell to pay

That was my point. Drilling and chamfering works for the RCBS seater plugs. I have also re-shaped the inside of a plug with JB Weld to prevent 'ringing' the bullet (Redding seater plugs). Forsters are usually pretty good with VLDs but the best (plug) is on the Lee Dead Length seater.

 

[gotcha]

Hey Kelbro, Don't drag me into this........ I'm just an innocent bystander. ??? Everyone is correct they just have different ways of expressing.

 

[JohnD]

Guys, thanks for the many replies. The bullet is seated with the ogive so it's not bottoming out. I rechecked the directions on the die setup and and I did make a slight
adjustment(depressing the chamber sleeve and backing out 1 turn before tightening the lock ring). Also, I thought I read once that someone said to take the spring out of the die because it didn't do concentricity any favors. Can someone confirm? Resized
case are less than .001 too.

Thanks again, John.

 

[CatShooter]

Guys, thanks for the many replies. The bullet is seated with the ogive so it's not bottoming out. I rechecked the directions on the die setup and and I did make a slight
adjustment(depressing the chamber sleeve and backing out 1 turn before tightening the lock ring). Also, I thought I read once that someone said to take the spring out of the die because it didn't do concentricity any favors. Can someone confirm? Resized
case are less than .001 too.

Thanks again, John.

I have the springs in all of mine (and my Redding comps too)... the spring keeps the cone of the shoulder forced into the cone of the sleeve, for consistent alignment, BEFORE the bullets starts to be seated.