Dasher fireforming and neck turning

[gmorganal]

I have a .272 neck fireforming barrel and just bought a new .2704 no-turn reamer from PTG. I was thinking that fireforming the brass first and then neck turning (just a clean-up pass) would be the way to go, but then I got to thinking that my Redding bushing resizer die does not resize all the way to the neck/shoulder junction. Will this create any kind of problem?

 

[canderson]

All of my dashers have been tight neck, so I had to turn on the front end. I do not for see any problems using your fireforming barrel. Try one and let us know.

 

[tripcrow]

I'd be sure to have the headspace on the new barrel set just a little longer than that on the fireforming barrel.
A Forster FL Dasher die is a not that expensive nice thing to have.
Be safe and check for head seperation after they are formed. Better than a third of my 30 Dasher cases had some signs. Found out when one split and near seperated on the first firing after forming. I will be using a false shoulder next batch.

 

[nosualc]

This sounds like it could be trouble to me...

When I've turned brass, I took fire-formed brass and ran it through a FL die (sizing the neck down), and then through the expanding mandrel (sizing it up) that came with my neck turner. I then turned the brass all the way down and a bit into the shoulder to avoid donuts.

The goal is to get the entire neck to the same inside dimension so that turning can be consistent, and any irregularities in neck thickness are on the outside of the neck wall, about to be turned away.

If the sizing step doesn't get the entire neck, then expanding step probably won't get the entire neck either. When you turn the necks you'll hit the unsized portion of your neck and take off a lot more than you want to. This sounds like a problem to me, maybe even a dangerous one.

I'd say you need a real FL sizing die.

My $.02; I await the opinions of others more experienced than I.

-nosualc

 

[gmorganal]

Thanks a lot for your responses, guys. I think a lot of how this plays out is going to depend on how much my Pumpkin mandrel enlarges the neck OD. If it makes it .272 or larger all the way to the neck/shoulder junction, do you see a problem?

 

[tripcrow]

Hmm. I'm thinking if he was to expand the cases to a 25 cal neck, then size just enough of the upper neck back down to a tight 6mm to the point where the bolt closes hard, fires them in the fireform barrel, then turns the whole neck to or close to the thickness he wants, then fires them again in the new barrel with .002" or more longer headspace, the bottom turned part of the turned neck should move into the new permanent shoulder junction. Don't think that little bit thinner junction would hurt anything.

Or is the new brass too thin to do it like that with a 272 fireform neck?

Edit: But I'd still buy a Forster FL 6 Dasher die. Just in ncase.