Confused about the Forster Coax

[battlecry]

I'm new to reloading and am trying to set up Redding dies on a Forster Coax press.

I'm confused about the proper way to set up the sizing die. The Forster instructions say to screw the die until it touches the shellholder jaw surface and set. Other brand say screw until the die touches the shellholder, add 1/4 turn and set.

Does the fact that the Forster uses jaws instead of a shellholder and that it stops at the top surface of the ring instead of the bottom one make any difference?

How would you set up a Redding sizing die on the Coax?

Thanks!

 

[Jim Watson]

I would set it up so the sized case fell between the high and low headspace marks on my Wilson case gauge.
If you don't have a case gauge, set a Forster press up by Forster instructions. Maybe they don't think they have as much slop and slack as other brands of press.

 

[taliv]

i also use case gauges, as jim mentioned. but for the 1 or two calibers i use that i don't have a gauge for, i would run it down until it stopped. however, i don't think you'll hurt anything by going another 1/4 turn, you just might not get as much concentricity. the jaws are supposed to float. it might be a trade off between sizing it as much as you want, but i doubt it. you should be able to do both

 

[Walkalong]

If you don't have a gauge, follow Forsters instructions.

 

[koja48]

Use the Forster instructions . . . I use a coax exclusively for rifle ammo & that's how I always set-up the dies. You want everything to "float," and going a "1/4 turn lower" (while it won't hurt anything) defeats that desired characteristic. Taliv is correct . . . you would compromise concentricity.

 

[battlecry]

Great. Thanks for the advice guys!

 

[ranger335v]

Setting dies by the "instructions" gives us ammo that will shoot. But it won't/can't give us the best ammo or ammo that actually matches our chamber. Even the Wilson gages only tell us if the case is sized within normal SAMMI tolerances and the rounds will work in all rifles but it can't tell us if it is the best match for our own chamber. Most headspace tolerances are around .007", more or less, and that's what a Wilson gage shows; maximum to minimum, only.

IF you want to actually match what YOUR CHAMBER NEEDS, get either the RCBS Precision Case Mik OR a StoneyPoint/Hornady case gage so you can see where the shoulder on your fired and then sized cases are. I prefer the RCBS Miks as easy to set up and read consistantly but both types work.

A quarter turn of a size die changes the shoulder (head space) almost exactly .018", over twice the proper tolerance for headspace! Such gross die changes are over kill and leads to potential head seperations. That's why so many "experts" say to toss brass after 5 loadings or so! (Turning a die 1/16 th turn moves the shoulder about .0045" and that's pushing the ideal headspace limits.)

I frequently load for 22-250, 243, 270, 30-06, 7 Mag and typically get 25+ loadings because I only size the shoulders back .001-.002", as gaged by a Case Mik, so this method of sizing works. (Okay, I also carefully anneal necks after each ten loadings)