I looked through quite a few reloading trays for .38 Special and .308 Winchester.

Some print poorly: the corner holes are too tight and prevent the cartridge case from being inserted. Others print better, but include protrusions that, in my opinion, are unnecessary.

When designing this model, I kept the following constraints in mind:

Fully customizable. Simple and basic design. Same design for all calibers.

So I’m offering this parametric model for use in FreeCAD.

Simply adapt parameters to your need:

• edge_spacing: the spacing on the edge of the tray
• tray_thickness: the thickness of the tray: the pocket for brass will be this v
• columns / lines: Number of columns and lines for the tray
• edge_round : How much to round the corner of the tray
• hole_chamfer : Chamfer size for the brass hole.
• hole_diameter: Diameter of the brass hole (i took 12mm for 38sp/357mag).
• hole_spacing : Space between each hole
• hole_pitch: "technical", auto-computed variable : space between center of hole
• tray_height / tray_width: auto-computed, height and width of the tray

Successfully tested on a Bambu Lab A1 Mini using the factory “0.12 Fine” print preset and transparent PLA+.