Case neck gauging for .223

[italian biker]

Hi all,
Not new to reloading, but new to rifle reloading. I'm going to start reloading for my AR. I know why you would gauge the case neck, but I don't know how. Can anyone give me a simple explanation, and suggestions on what gauge to purchase?

 

[243winxb]

Cartridge Case Gage

You may be using the wrong term. L.E. Wilson makes a cartridge case gage to check loaded ammo or fired brass. But an RCBS Precision Mic is a better choice and will do more. If you just want to check neck diameter, just use a micrometer. Here is some good reading that may help you. http://www.brownells.com/aspx/NS/GunTech/NewsletterArchive.aspx?p=0&t=1&i=1305&mc_ID=2019

 

[italian biker]

whatever the thing is with the round needle gauge thingamajig.

 

[243winxb]

would it be this? http://www.6mmbr.com/casenecktools.html