yep, the crimp only forms correct when it's mooshing down onto a shot charge.
Some sort of hollow tube that would fit inside just right with a solid end could be crafted up but seems like a pain.
Now, a roll crimp might be a little easier, but same problem.
then the light wouldn't be able to shine thru.. hmmm...
you know, some 3/4" or 5/8" clear plastic tubing with a nitro card on top would work I would think?