Hey Coach!
I wish I would have checked the posts earlier. I just finished my first cartridge pen (no picture yet). Using 30.06 casing and antler.
1. I prepared the antler and glued in a slimline tube and milled the ends set aside. (easy)
2. I then popped the spent primer out using a 1/16" ss welding rod. (easy)
3. I then drilled a 9/32" (don't have a 7mm metal working bit) hole through where the primer was all the way into the casing chamber. (hard to get perfectly centered due to poor skills)
4. I then took a "messed up" European and took the bottom half of the blank and turned it straight like standard slimline the the same diameter as the portion of the casing that holds the bullet. (easy) (The lower tube for a Euro is pretty close to the same length as the casing, close enough anyway [
] )
5. I then turned down to the brass tube to make a tenon that would slide into the 9/32" hole that I had made in the casing head. About a 1/4" from the end of the tube. (easy)
6. I then inserted/wiggled the tube into the casing from the necked down end until it was flush to the end of the tube. (easy)
7. I put a couple of drops of thin CA on both ends hoping that capillary action would pull the CA into the joint. (it did [
] )
8. After a few minutes for drying I put the casing on the mandrel to polish. Wet sanded with 600 grit and then polished with "NeverDull". It left very fine lines, which I liked. I then waxed the casing with Turtle Wax (should have used clear laquer instead, oh well)
9. I then finished turning the antler to the diameters I wanted and polished (no finish).
10. I then assembled the pen as normal, pressing in the nib first and then the mechanism.
It turned out pretty decent, I just have to do better at drilling that hole through the casing AND finding a 7mm metal working bit.
I have to give credit to Eagle though. He is the one who inspired me to do this. When I saw his pen I just had to try one.