Single Stage Reloading Press Shootout {14 presses tested}

[T-shooter]

A lot of information here. The 1st link is the video (41 minutes) and the second, not a video, is more in depth showing tools and methods of testing.

https://ultimatereloader.com/2019/04/08/fourteen-reloading-presses-compared-single-stage-shootout/

And a link to the pressure force gauge he is using. For that much money, I really don't need to know.
https://www.amazon.com/dp/B008YMIZ8A/?tag=accuratescom-20

 

[JimSC]

I was taught that the overall tolerance in a machine is the largest tolerance of the components of the machine, in a press that would be the float in the case has in the case holder or die holder in a co ax. Seems to me if the case sitting in the case holder has .1 inch or more of float in the X, Y, and Z axis then .000001 or .01 slop on the ram is moot. The force measurements were interesting though.

 

[59FLH]

I was taught that the overall tolerance in a machine is the largest tolerance of the components of the machine, in a press that would be the float in the case has in the case holder or die holder in a co ax. Seems to me if the case sitting in the case holder has .1 inch or more of float in the X, Y, and Z axis then .000001 or .01 slop on the ram is moot. The force measurements were interesting though.

The clearance in the shell holder is to allow the center axis of the die and case to align maintaining concentricity, slop in the ram will cause "Tilt" and potentially miss align the axis .

 

[JimSC]

The clearance in the shell holder is to allow the center axis of the die and case to align maintaining concentricity, slop in the ram will cause "Tilt" and potentially miss align the axis .

I agree on the reason for the shell holder clearance, disagree on the ram tilt theory. The sizing operation is a fundamentally a cold extrusion process, once that shell casing is fully inserted into the sizing die a small amount ram clearance cannot cause any misalignment. The only time any misalignment of the neck can occur is when withdrawing with the expander button in use which can, and will in my experience, cause the neck to misalign. But that is due to uneven friction between the button and the inside of the neck with no lateral support for the neck from the die walls. Don't take my word for it, at the top of the sizing stroke remove the pressure and see if you can move the case even .00001 inch. The case is in a interference or press fit at that stage and fully supported from the base to the neck by the interior of the die. You would have to bend the die to bend the neck at that point

 

[T-shooter]

A button or ball is not necessarily a bad thing. I use Forster bench rest full length dies. The spindle can float a slight bit from side to side allowing it to align. Second, if it is adjusted properly, most of the neck is still in the neck portion of the die when the balls starts to be pulled through. This works much better with neck turned brass because the neck is centered in the die and inner diameter is also centered, not offset because of thicker and thinner sides of the neck. To set the height of the ball, I run a neck turned case (after trimming the length and neck turning) all the way into the die. Then raise the ball until I feel it touch. Turn the ball and spindle back down 1/4 to 1/2 turn and lock in place. If you have it too high it will lock up the die. The runout on my brass usually runs under .001" measured in the center of the necks and the inside diameters are all very consistent in internal diameter.

 

[Depart123]

Side note:
Forster and RCBS spindles are different, but the spindle bushings have the same exterior threads.

I turned a few vintage RCBS dies into match dies by spending $16 or so on a Forster assembly and screwing it into the RCBS dies.