Eye opening tool

[Barlow]

I know I'm preaching to the choir here, but I bought a ball mic a few weeks ago and wondered now how I ever got along without one. I tried to measure neck thickness with a good caliper and thought it was accurate enough. Well it ain't, least ways, not for me. So all you guys out there who are just starting to handload or like me have been at for years, I highly recommend you invest in a ball mic. jmo Barlow

 

[tenring]

And get one that measures to .0001" or .0002", i.e., Starrett, Sharpe & Brown, Mitutoyo, etc.

 

[gilream]

I know I'm preaching to the choir here, but I bought a ball mic a few weeks ago and wondered now how I ever got along without one. I tried to measure neck thickness with a good caliper and thought it was accurate enough. Well it ain't, least ways, not for me. So all you guys out there who are just starting to handload or like me have been at for years, I highly recommend you invest in a ball mic. jmo Barlow

+1

 

[mikecr]

Also make sure you install a stop on the mic anvil so that you're measuring at the same neck depth(all the way around, case to case).

 

[jonbearman]

Would you have a picture of that stop you use Mike?

 

[mikecr]

Anything similar to this

 

[jonbearman]

Mike did you make that or was it factory ?

 

[Road_Clam]

Why is a ball mic preferred in measuring necks ? Does the brass neck bore o.d. become belled ? (sorry newbie here looking to soon engage in handloading)

 

[fdshuster]

Road_Clam: It's impossible to measure the thickness of a case neck wall (a tiny section of an arc) with a measuring instrument like a dial caliper that has a flat contact surface.

For anyone who wants to try a tubing micrometer, Lyman makes a very good one (yes, it's "made in China") at the reasonable cost of around $50. Midway master catalog #35, page 298. I bought one when they first came on the market and it got the job done. It does have the ability to read to .0001", or very close. Since then have upgraded to a Mitutoyo, but still use the Lyman on occassion.

 

[Road_Clam]

Road_Clam: It's impossible to measure the thickness of a case neck wall (a tiny section of an arc) with a measuring instrument like a dial caliper that has a flat contact surface.

For anyone who wants to try a tubing micrometer, Lyman makes a very good one (yes, it's "made in China") at the reasonable cost of around $50. Midway master catalog #35, page 298. I bought one when they first came on the market and it got the job done. It does have the ability to read to .0001", or very close. Since then have upgraded to a Mitutoyo, but still use the Lyman on occassion.

Ahh, ok now I get it. I do CNC machining and could not understand exactly what and how you were attempting to measure. If you need tight consistant accuracy #'s a tube mic is the only solution.

 

[Barlow]

I bought the RCBS dial model .0001 accuracy. It takes a little while to get used to holding it correctly, but it works great. Barlow

 

[Smalltruck]

Uhhh lots of you are stating get one that measures down to .0001. That means it measures to the ten thousandth of an inch. do you mean measures to the thousandth of an inch or .001?

I ask because I'm guessing the price will not be cheap.

 

[mikecr]

.001" isn't accurate enough. Remember we're affecting neck clearances.