Step 1: Drill Out the Primer Side
What you’re trying to do here is replace the body of a regular click pen with a couple shell casings. Keep mind I figured out this process by trial and error. If you do the steps out of order you may ruin the shells and have to start over.
You’ll have to drill out the primer ends of both shell casings. I used a mini metal lathe with an 11/32 drill bit chucked into the tail quill. You could use a regular drill but the tricky part is finding a way to hold the shell without distorting it. Once you have both shells drilled out, you’ll have to expand the necks. Before can do this you need some measurements.