Ball micrometer vs Horandy Neck Wall Thickness Gauge (spindal, pilot) adaptor

.30-06

Well-Known Member
Joined
Apr 14, 2022
Messages
172
Location
NJ
I have a ball mic and wondering is an indicator and pilot would be better.
 

Mikecr

Well-Known Member
Joined
Aug 10, 2003
Messages
6,190
Location
NC, oceanfront
No, a pilot does not provide true spot measure like a ball anvil.
This matters (functionally) because necks taper in thickness, including a donut area thickness. So with a pilot, you would read an average thickness from shoulders to mouths, rather than actual thickness at each chosen datum.
You don't want to add that thickness taper to your intended thickness (pure) reading.

Necks can also vary in form (with taper). An indicator will not press out that form against a pilot.
 
Last edited:

.30-06

Well-Known Member
Joined
Apr 14, 2022
Messages
172
Location
NJ
No, a pilot does not provide true spot measure like a ball anvil.
This matters (functionally) because necks taper in thickness, including a donut area thickness. So with a pilot, you would read an average thickness from shoulders to mouths, rather than actual thickness at each chosen datum.
You don't want to add that thickness taper to your intended thickness (pure) reading.

Necks can also vary in form (with taper). An indicator will not press out that form against a pilot.
The pilot just supports the case, but I shouldn't have to tell you that. It doesn't make a difference if it's indicated inside or out side. I used RCBS, and other tools to indicate and they all measure the same with the exception of the ball mic. It's not that complicated Mike.

On another note, I'm not trying to come here to start an argument but instead just input on what are reasons why you would choose one over the other and so far the reasons are not supportive enough.
 
Last edited:

.30-06

Well-Known Member
Joined
Apr 14, 2022
Messages
172
Location
NJ
I think I'm satisfied that the Lee neck collet sizer has me at within a ~.0015-.002 neck runout and at .013 to .0135 neck thickness from .013 to .0145 with a ball mic.
 

Recent Posts

Top