Forster co-ax press question

T

tangolima

New member
Have been thinking about upgrading my old Lyman T-mag. The co-ax seems a good design, although it's a bit unconventional. I really like the spent primer catcher.

But after reading the manual, a concern surfaces. The automatic case jaw works with rim diameter of 0.310" or bigger. The smallest cartridge I am Handloading is .25acp, whose rim diameter is slightly smaller than 0.310". I don't want to use their adapter in order to use the universal shell plate. What do you think if I grind away the shoulders of the jaw just a tad, so that the jaws can close up just enough?

Your suggestions and comments are much appreciated.

-TL
 
I have the Forster co ax and love it. The auto jaws have a small end and a large end. To change from one to the other, you remove the Allen screws, remove the top cover plate and swap the sliders end to end. Replace the plate and reinstall the Allen screws. They even mark an S on the small end for those that need a little extra boarding time....lol.

When I bought mine, it came with the S plate which I described above. You will want the LS in addition I believe. I ordered mine from a place in Oregon or Washington. Midway has them and the extra parts you would need. Do not order directly from Forster, costs twice as much.
 
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Are you sure the LS doesn't have a smaller end vs the S?

"Please note that some cartridges, .38
Special for example, will be gripped
by both ends of the “S” Jaws.
“LS” Jaws P/N 001251 is an optional
set of jaws sold separately. It was
developed to accommodate a wide
range of very large & small case
heads:
Smaller side will handle 22 Hornet
and other small case heads.
Larger side will handle 256 WinMag,
348 Win, 378 WBY, 416 Rem,
416 Rigby, 45-70, 45-90 and other
large case heads."
 
One down, a few more to go.

The jaws are kept shut by a pair of springs. It doesn't seem as rugged as the conventional shell plate, does it? Will the brass rim slip over when there is need for a strong pull to free a semi stuck case in the die?

Same as the way the die is "attached" to the press? It relies on the lock ring, which hardly has 3 turns of threads. Can it hold up during a tougher resizing session, say reforming 30-06 to 8mm Mauser?

-TL
 
Same as the way the die is "attached" to the press? It relies on the lock ring, which hardly has 3 turns of threads. Can it hold up during a tougher resizing session, say reforming 30-06 to 8mm Mauser?

First let me say I love the Forster .

I have no idea how you came up with this . It does not have just three turns of threads . The Die snaps in and works very well can change dies as fast as you can use your hands . I went from an old RCBS to the Forster it is just as heavy but faster .
 
The presses and dies and heat treated jaws have way more strength than is actually required. I tore the head off a stuck .223 case with mine, and the jaws show no sign of the event.

The reason for the overbuilding is the extra rigidity makes for better consistency with match ammo and other precision applications.

If you feel more comfortable with it, Forster makes an adapter for using conventional shell holder in the Co-ax press. But doing that, you lose out on one of the presses features, which is the jaws have a little of the wiggle in them that contributes to self-alignment with the die.
 
What they said! ^^^^. I reload everything from .223 through 7mm Rem and300 win mag. I load literally hundreds of .308 and 30-06 each a month. I have had this press for almost 4 years, never a problem....I did bevel the upper end of the primer catch tube for better falling of the spent primers.
They used to be known as a Bonanza Co Ax and have been around for at least 50 yrs and most still going strong.
 
KEYBEAR said:
I have no idea how you came up with this . It does not have just three turns of threads . The Die snaps in and works very well can change dies as fast as you can use your hands .
Click to expand...

I think I didn't explain clearly. There is a groove in the upper frame to accommodate the lock ring. The die threads in the lock ring. The weakest link is the lock ring. It is probably 1/4" thick and has about 3 turns of threads inside. My Lyman has a turret of about 3/4" thick.

Do I understand it correctly? thanks.

-TL
 
I'm thinking you should stick with your lyman turret press if you are concerned about that 1/4" ring letting loose. Have you heard of anyone that had that happen? Have you done a google search on the subject? Has anyone here mentioned a problem with that? I think maybe the red paint might be a major problem, some have mistaken it for Rudolf and taken a shot at it.
 
Unclenick said:
The presses and dies and heat treated jaws have way more strength than is actually required. I tore the head off a stuck .223 case with mine, and the jaws show no sign of the event. .
Click to expand...

I have no doubt on the heat treat. That's not my concern. The jaws are movable, and are kept shut by a pair of springs. The flange in a conventional shell plate is fixed. Think crescent wrench versus fixed wrench. If the extraction groove in the brass is not positive, it will try to push the jaws open. Here the weakest link is the springs.

No I don't want to use the shell plate adapter. That would be silly.

Thanks everyone for your inputs. I have no doubt you love your Forster. I want to be the same too. But it is what it is. It is solely technically discussion. I look at the pictures and drawings as an engineer and ask questions as I see it.

-TL



Sent from my SM-G930T using Tapatalk
 
Jag, I ran across that one some time ago and forgot about it. I remember the guy having a real question about why anyone would even think it was a weak link....thanks for throwing that out. LOL.
 
Thanks for the YouTube link. Good information.

I did the calculations myself. One turn of 7/8" -14 thread in aluminum can withstand more than 5,000lb of force before shearing. I think that should suffice.

Based what I have heard so far, it seems the design is sufficient for all normal reloading needs.

Final question if I may. Has anyone here used it for case conversions? Say converting 30-06 brass to 8mm Mauser. It is pretty taxing on a press' strength.

-TL
 
There are stainless lock rings available for the Forster, I have some, but you're gonna play #%$@ pulling your die through an aluminum one. :eek:
 
I wasn't referring to any particular video. Go to youtube and do a search for Forster press. There are a bunch of them. If there is a weak point in the Forster its the operator. Believe me, I know.
 
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