Forster co-axial press

zoeper

Well-Known Member
Joined
Feb 20, 2008
Messages
85
I need to upgrade my current press and am considering the Redding big boss and the Forster co-ax. Apart from the sales brochure hype, is there any real advantages to choosing the co-ax above the big boss?
 
Don't know anything about the big boss, but I replaced my old RCBS with a Co-Axial 2 years ago. I like it so much better. Set all your dies up 1 time and never adjust again
 
Your question touches on an issue not unlike religion. Both presses are very well made, and both do essentially the same job. Whether any difference is real or merely perceived is hard to determine. You could buy both, compare,and return the loser. Someone on another forum reported on that scenario. The discerned difference was that cartridge length could be varied on the Big Boss by using varying levels of seating force, flexing the stops on the Big Boss, not necessarily a real world issue. While some have reported superior cartridge run-out results with a Co-Ax, in this incident the Big Boss was it's equal. These two presses were also compared to a RockChucker Supreme; it did not fare as well.

The Co-Ax has unique ergonomic characteristics; the press is more easily operated from a standing position. It's universal shell holder is inconvenient to change over when necessary. The press will not accommodate oversized die threads. Bullet pulling requires special considerations.

In the end, the press you choose will depend on what appeals to you. You have complexity on one hand, and simplicity on the other. The Co-Ax is the last H-frame press mass produced. The Redding press is the best of its design. Toss a coin as a provisional selection; then you can determine your level of satisfaction with the outcome. The choice is easily changed. What do you like?
 
Last edited:
Thank you all for the replies.
Win 69 - I was told by a very knowlegable and respected gunnut in local circles - who happens to sell a lot of both these presses - that he would much rather spend the extra$ and upgrade to the co-ax. Main argument being the alignment that is (automatically) controlled by the case and not the press, and that this results in less runout.
The upgrade would involve:

new press
new set of redding competition bushing and seating dies
meaning that i would also have to start doing outside neck turning and would have to invest in those tools as well

for now i would easily fall for the big boss (same style as my current press), but i'm just scared that i might miss out on some "magic"................(i did read in another thread on this forum that there is "no magic" involved)
 
...the alignment that is (automatically) controlled by the case and not the press, and that this results in less run-out.
There is enough latitude in the shell holder of a standard press that the case aligns itself to the die routinely. Some remove the wire retainer and replace it with a rubber O-ring to allay all doubt. The two critical elements are ram play (lack of) and die alignment. You won't go wrong with either press. It's a matter of evaluating the trade-offs (ergonomics and limitations) of the designs, and then deciding which really appeals to you.

As an aside, Glen Zediker, noted reloading and shooting guru, wanted a press for seating bullets at the range. He chose the cheapy Lee C-press. He floated the die in the frame, using rubber O-rings both under the die and to retain the shell-holder. That press with all of its slop and imprecision is the last one I would choose. He was perfectly satisfied with his run-out. He now represents Forster, but I doubt that he hauls a Co-Ax to the range (it probably just replaced his old Boss). He uses an aluminum turret for that purpose. I haven't said it, but perceived desirable results generally follow the choice of equipment, ruling out obviously poor choices or defects. People tend to be happy with what they buy, reinforcing their purchasing decision.

I use a Redding Boss and feel no need for anything else. If someone gets warm fuzzies from owning the Co-Ax then he knows what makes him happy. I would pay close attention to ergonomics; it's what you'll really be living with. But go with the one that makes you happiest; that's the most critical element.

The dies don't determine the desirability of neck turning. Having a tight-chamber barrel permits the fitting of the case neck to the chamber, and that requires neck turning. Many use the Lee collet die for factory barrels.

As a suggestion, you may want to obtain a copy of Zediker's book, Handloading for Competition. It's available from Sinclair or Zediker directly. If you get it from Sinclair, you can request their catalog. Reading it before making a choice may make sense; you'll carry more information into that process. It's difficult to read due to Zediker's writing style, but also it's very informative.
 
Last edited:
My point exactly. The one you choose is the one you'll love.

I still think the simplicity/complexity thing is the determining element.
 
"I was told by a very knowlegable and respected gunnut in local circles - who happens to sell a lot of both these presses - that he would much rather spend the extra$ and upgrade to the co-ax. Main argument being the alignment that is (automatically) controlled by the case and not the press, and that this results in less runout."

If any press is bored and threaded perfectly and the dies are perfectly mounted and the ram has zero side play concentric ammo can be made on it. But, in real life such things are rarely perfect. If the alignments are not perfect, we can use the Co-Ax press, with it's floating die holding method, and get concentric ammo every time. If our press is not perfect we can play with largely pointless tricks such as using rubber rings to retain the shell holder, which can only allow shell holder movement in one direction, and we MIGHT get concentric ammo.

But, in ANY press-to-ram fit that has a bit of slack (slop), the case can easily SELF align to a die as it enters, as precisely as in a Co-Ax with it's floading dies. Meaning, the popular myth of a truly tight ram-to-body fit is badly misplaced.

ALL that a super tight press CAN do is force a bad fit, it's really no mechanical help in obtaining a precise fit at all. Sized cases with bannana shapes come from tightly fitted presses, not old, "worn out" presses.

BR shooters with their hand dies and arbor presses have the ultimate in "sloppy fit". But their totally floating die and ram system insures they get a maximum precision fit and accuracy without ANY rigidity of alignment.
 
Last edited:
I have both a co-ax and a k&m arbor press. Each work great in different situations. I feel that the primer seater on the co-ax is pretty darn close to worthless. I do feel like I get quite a bit of "feel" when resizing in the forster press. The forster also has a nice primer/debris catcher that is nice as well. I can easily make ammo with near zero runout, however, I have just as easily made ammo with 10-15 thou runout on the same press. I chose the co-ax, but I understand its limitations and use it accordingly
 
Conventional presses, with the fulcrum attached to the bottom of the ram, and cantilevered on the opposite side of the ram bearing from the shell holder, by necessity, will advance the cartridge in a vertical arc, or at the least, not a straight line. The alignment of the cartridge to the die is thus a dynamic issue, and must be adjusted throughout the stroke. The ability of "float" to re-align the cartridge with the die is limited while force is being applied due to friction in the floating systems. The user can overcome this by pausing once or twice while advancing the cartridge into the die, allowing pressure to subside, and the floating systems to do their job more easily.

The co-ax supports the shell holder & "ram" between bearings above and below, avoiding cantilevering. The co-ax fixes the fulcrum to the press frame, not the ram. The co-ax linkage applies lateral force to the shell holder in one direction only during the stroke. Thus, all play in the ram is taken out uniformly and consistently throughout the stroke, resulting in a straight line vertical travel, making it easier for the floating systems to adjust the alignment of cartridge to die.

As with many things in reloading, technique has as much to do with accuracy of results as equipment does. Some equipment makes the necessary technique easier to apply.

The Redding Big Boss is an excellent press, but I would consider the Big Boss II variant more desirable, since it has a hollow ram to allow spent primers to be captured more consistently and easily. The co-ax takes that one step further, since it does not have a priming arm in the ram, it never allows primer debris near the bearings of the press while efficiently depositing them in a catch bottle.

As mentioned earlier, the ergonomics of the two presses are quite different. Most users prefer to use the co-ax while standing, making it easier to deal with the handle travel down the center. If you prefer to sit while using your press, this may not be the best for you. I personally like the higher position of the co-ax handle and its range of motion.

As with all things, YMMV, etc.

Andy
 
Warning! This thread is more than 15 years ago old.
It's likely that no further discussion is required, in which case we recommend starting a new thread. If however you feel your response is required you can still do so.

Recent Posts

Top