Hi Michael,
I might as well put my two cents in here as well.
I'm sure everyone does them a little differently. Some drill out the projectile end, and some don't. But they all come out looking very nice.
I buy new casings. They aren't very expensive, and then I don''t have to knock out the primer. I use just the empty casing.
The 308 is in my opinion a good one to use because the brass tube that comes with the slimline pens is almost a perfect fit for length. The 270 and 30-30 are good ones also. If you want to use the brass tube I mentioned.
The 30-06 is a good one also, but they are longer. So if you use the brass tubes as a guide you would have to get some of the longer ones and cut them to the length you need.
Currently I use a 17/64 drill bit to drill out the back side. It is just a little small, so I take a round file and and file it by hand. It doesn't take too much filing. Or you can go up one drill bit size. I don't have any metric bits, or numbered bits. But they would be good.
Now on the projectile end of the casing it gets a little trickier. With the 270 the brass tube fits real nice. With the others the opening of the casing is a little bigger than the brass tube so you need to do something to help center the brass tube. And here is where everyone does something a little different i'm sure. This is based on talking to several different ones. So try different ideas.
What I have been doing lately is wrapping teflon tape around the end of the tube to take up space. Not all the way to the end. Hold it back about 1/4 of an inch or so. There has to be a better way, but i'm not sure what it is at this point. Because we are not talking about a lot of space here.
Then I run gel type CA around the inside of the butt end of the casing and slide the tube in from the front, just to the end of the casing. And set it upright on some waxed paper.
Then I run gel type CA glue around the opening and let it flow in between the casing and the tube. Don't be sparing.
And give it plenty of time to dry. And you may have to grind just a little off the front end of the brass tube.
Now for the upper barrel I use different things. Antler, wood, sometimes a combination of shell casings and antler, or various things. I have been doing some lately using purple heart for the upper barrel. But here again if you use the slimline brass tubes go for the length of the tubes with whatever you want for material. You can even make your own center bands if you wish, or let it butt up to the shell casing.
The one thing you have to watch for is the outside diameter of the pen nib, verses the outside diameter of the shell casing. To try and get the best fit, here.
Top it off with a rifle clip, or something else of your choosing.
Harry
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