Pretty easily made using an old golf club if you have one laying around. If not head over to a Goodwill store or look around in garage sales for one.
What I did was heat up the head so that the epoxy melted enough to pull the shaft out. After that I cleaned up the insides, and used my digital caliper to measure the thickness. I then just worked my way up the outsides until I got to the size I needed and used my dremmel tool with a cut off blade in it to chop it right off. Take a file and chamfer tool and clean up the end so it is square and deburred and then all thats left is to cut to a comfortable to use length.
If your lucky and find one of the older shafts that is graduated about every 6 or so inches to a larger size it makes it real easy to cut it maybe a half inch or so above the proper size, then when your shoving it down over you bullets, they simply run right up the middle and you can get 6 or 10 before having to dump it out.