longrangefreek
Well-Known Member
watched the show and really enjoyed it.
I got to watch the show tonight. All it all it was pretty decent. The shot directly into the sun was a little hard to see but after I rewound it about 3 times I could just catch the bullet wash going out a. The cnc barrel set up was interesting. I'm still trying to figure out why the range rod was held in the tail stock though. I wish the best to both Aaron and Mike for putting together a long range tv show.
I couldn't understand why it was held in the tailstock because most every tailstock is not dead on center of the spindle axis. I've adjusted and shimmed my tailstock so it's indicated dead nuts but if I remove the dead center, slide the tailstock back and forth then lock it back down even with the same torque spec. it's out a little. If your indicating off of the barels bore than the indicating rod should just be in the barrels bore not acted on by the tailstock. Maybe I'm missing something but it just doesn't make sense to me. I know there's a dozen different ways to chamber a barrel, not all of them are wrong, just different. As long as your getting good results in the end something must be working right.
I use PTG's indicating rods that have a removable pilot to fit the bore precisely. I hold the barrel in a fixture I built that has 8 brass capped set screws simliar to that of GTR's action blueprinting fixture. I'll put 2 .0001" indicators on the rod. One right where it comes out of the barrel and the other about 5" down the indicator rod. By manipulating the 8 screws I can dial the bore true to my spindles axis to within .0001" on both indicators. If I only used 1 indicator say right at the barrel and dial it in true, the barrel is not truly dialed in and can be in a cone with the point at where the barrel contacts the screws as the fulcrum point.