6BR FL sizer die shoulder setback issue question

[SheepDog]

Yep, if it's too tight it can change the geometry of the shoulder. To fix it I honed the bore of the sizer and polished the sizing button. I wasn't sure how far to go but a little at a time until the problem was solved.

 

[Linko]

Drum Roll Please......

the Co-Ax press comes with 2 jaw sets. "S" & "LS". I checked the Forster manual and they provide a dimensioned drawing of the jaws. I was using the "S" set. The drawing shows the depth of the milling of the "LS" jaw at the portion that grabs the case head to have a deeper cut (.070" vs .056). So the top is thinner and there for, the die can get more of the case into the die. So far this looks to provide the slight setback I am looking for.

 

[savagedasher]

I wouldn't re design the press . I would shorten the dies like we have had to do for years . Like every gun I have had that I had a tight head space . Larry

 

[Linko]

I wouldn't re design the press . I would shorten the dies like we have had to do for years . Like every gun I have had that I had a tight head space . Larry

The jaws were just a means to verify the issue. I will have to send it back to Whidden to shorten the die. I have no means to do that work.

 

[Richard Jones]

Doesn't the die bottom out on top of the shellholder, regardless of jaw selection? Only if the shellholder plate thickness decreases can more case get into the die.........

I'm not following how swapping shellholders is going to change anything....... confused.....

 

[Linko]

Doesn't the die bottom out on top of the shellholder, regardless of jaw selection? Only if the shellholder plate thickness decreases can more case get into the die.........

I'm not following how swapping shellholders is going to change anything....... confused.....

if the case bottom is shimmed the LS jaw is thinner than the S. .070 vs .056

I spoke with john whidden and I am getting a go gauge to see if my chamber is shorter headspace than sammi.

 

[Richard Jones]

if the case bottom is shimmed the LS jaw is thinner than the S. .070 vs .056

I spoke with john whidden and I am getting a go gauge to see if my chamber is shorter headspace than sammi.

Gotcha. I "retired" the issued shellholders and use standard ones now. Keep us posted on the 'fix'.

 

[Linko]

I received my Go-Gauge today. I checked to see if my chamber is shorter than Saami spec, it's not.

I used the LS jaws and am able to set back the shoulder .005 , I should be able to get more, but that's it for now. I will fire my next loads with that headspace.

 

[Linko]

Related article


http://www.accurateshooter.com/technical-articles/die-issues-when-bumping-shoulders/