I heard a few say that the gage does not come back to zero or that there is a difference in reversing the gage taking it out of the bore. You have to remember that the holes for the ball bearngs are size on size, and any minute piece of dirt will stop the ball from seating giving you an errouneous reading.
As far as withdrawing it and getting a .001 difference, is that such a big deal? Again the balls are rotating in their fit and any type of dirt will give a bad reading or make it jump.
I tried making a smaller head for 20 ga. out of aluminum as a prototype. Trouble is I need to get smaller ball bearngs, as I tried using the same .250 (1/4") balls that are in the Skeet's. I can only get two in because the I.D. is to small for these balls. I'll try .1875 (3/16") so that the holes can be reamed to size. They naturlly have to be put in from the inside.
The inner aluminum tube is still 3/16" dia. and I guess it is easy and cheap to use the phenolic outside tube.
It might be easier to make a 10 ga. head and still use the same .250 ball bearings.
In my previous post about setting the dial indicator to 1 (.100), I was wrong, the worker told me to set it inbetween the range (0-500) and so I set it a 3 (300). This is to give you enough travel.
Last edited by JDW; 03/15/11 10:03 AM.
