UPDATE 2 2/24/2018
After performing a test print of the cap and threads I found them to be difficult to thread together, I have reworked the cap to allow for more room for the threads. Updated both V1 and V2 caps. Either will work
UPDATE 2/24/2018
I have included a modified version with notches cut out to allow for better adhesion when gluing, this also allows you to forgo the rod and just print glue and snap together giving you a cavity in the center to place any objects that could fit, such as BBs
Yet to be tested, but this is a remix of DragonflyFabrications Replica Stielhandgranate. I split the STL files into separate pieces to allow easier print ability, a also modified the model for a screw on lid as the real Stielhandgranate had. This will allow you to add rope like the real one or even allow you to now store BBs in it. I may modify this further for better functionality and fitment.
I recommend printing the cap and screw base at .1 with high infill and the rest can be printed with .3 and low infill.