When using the Sinclair expander mandrel with .223 Remington the case can hit the mandrel pin or go up the side of the pin which damages the case, when used with 300AAC blackout the body of the die is to long for the mandrel to fully resize the case neck. This mandrel die having a smaller hole with an entry guide as well as being shorter cures both of these problems. The .223/300 AAC has been tested and worked perfectly. The 243 and die body with the standard hole have not been tested but should work.
Due to the stress on the layers when in use I used PET-G and would recommend a filament that has good layer strength.
I have tried 308 winchester in the die but brike it when i forgot to lube the case mouth.

Probably works with other cases of a similar size

Prusa

i3 MK2 MMU

No

No

.2

100%

Strong filament with good layer adhesion required, high infill used to increase strength and give larger surface to increase layer adhesion.

die can be slightly larger (elephants foot) at base causing the thread to be tight, running a metal nut from the top to the bottom usually cures this