Originally posted by lawndart:
I had a productive afternoon at the lathe today.
I have long used the Hornady (Originally Stoney Point) Chamber-All case gauge system to find out the cartridge case's head to ogive length. Then you can figure out how to set up your dies for your choice of distance off the lands. Part of the Drill (Ha, Ha) is to take a case that has been fired in your Chamber. Then you need to use a set of dies for disassembling your cartridges to help you run a bullet into the neck multiple times so that there is some grip, but not too tight. Then you can use the hornady "Slider" to help measure the base to Ogive measurement. Then you can make a dummy round for full engagement into the lands
With That Bullet. Then you can make a dummy case for 0,005", 0.010," and so on off the lands. Once you figure out the "sweet" distance off the lands, just go with that case.
Needed for producing an altered case are:
1. A size "L" letter drill.
2. A 5/6-36 Tap.
Yeah, I thought the sizes were screwy too. Here is the procedure I followed with great success today:
1. Chuck the cartridge case in the Three Jaw with the case head centered, and sticking out of the jaws.
2. Chuck up the "L" drill.
3. Set the speed at 270-400 RPM.
4. Secure the 0.290"/L/7.3mm drill in the tailstock. No lubrication.
5. Feed the drill all the way in, and then pull the bit out.
6. Remove the drill bit, and chuck up the 5/16-36 HSS Tap in the tailstock chuck.
7. At 70-100 RPM, feed the Tap into the case head. It will be drawn right in.
8. Turn the lathe off. Then select reverse, and turn the lathe back on. It will spit the Tap out just like a good Catholic girl.
9. Go over the Tapping procedure two more times by hand.
10. You are done. My references state that a small bench top "Hobby" lathe gives superior results. I don't know that to be true, yet, but I will find out on my old "Shop Fox" lathe (Taiwan model is what I have).
I am going to do this with some 416 Rigby, 416 Rem Mag, 404 Jeffery, 470 NE, 9.3 x 92mm, and you get the idea.
If the hobby lathe works well, I will have to consider making cases for people without access to lathes for a nominal fee. Least I can do for all the help board members have given me.
Monthly meeting of the First Wives Club (FWC).