RCBS Precision Mic

Discussion in 'Reloading' started by mtelkhntr78, May 20, 2009.

  1. mtelkhntr78

    mtelkhntr78 Well-Known Member

    Dec 30, 2008
    Has anyone used the RCBS precision mic for measuring headspace? I got one a couple of months ago for my 30-06 and have been testing it out.
    Frankly I have been less than happy with the tool. It also comes with a gauge to measure OAL. That thing has just about driven me to insanity. Very difficult to get an accurate measurement out of and just generally a pain. The mic for measuring headspace works ok but I have since bought the Hornady tools for taking those measurements and they work alot better.
    Has anyone had good luck with the precision mic? I used to be an RCBS fan but lately I get less and less impressed with their equipment.
    Last edited: May 20, 2009
  2. MagnumManiac

    MagnumManiac Well-Known Member

    Feb 25, 2008
    Yes, I have them in .222, 257Roberts, 25-06, 270, 300WinMag and 338WinMag. They are a simple tool to use once you understand their pitfalls.
    You have to have a light 'touch' for them to be accurate, just like a micrometer, but once you have it "down pat", they're very repeatable.
    I can't say that I've used the COL part of it extensively, because I use the actual bullet for this, each bullet has a different ogive shape and length, which is what should be used to set base to ogive length.

    I am yet to fault it, each to their own, I guess.

  3. boomtube

    boomtube Well-Known Member

    Oct 8, 2007
    The shoulder and ogive thimbles are great tools. The "free bore" tool part, the dummy cartridge, is not.
  4. WRG

    WRG Well-Known Member

    Nov 25, 2008
    mtelkhntr78, your absolutly right it is junk and RCBS knows it. I called them about it one day and all I got was blah blah blah. When it comes to reloading equipment and all the different manufactures they all seem to have their good tools and bad tools and this is a bad one from RCBS. If you want a good headspace gage try going to this website www.larrywillis.com In my opinion it is the best there is hands down. It is the easiest, fastest, and most accurate gage there is. Headspacing is the most important step of reloading. I don't know how anyone could set up a sizer die correctly without knowing how far they are bumping the shoulder back. You only need 0.001 HS clearence any more than 0.002 and your over working your brass needlessly.

    If you want a good tool to measure OAL make it yourself. It will cost you nothing and will be the most accurate tool you will own. Take a fire formed case for whatever caliber your working with. Cut four slots down the neck with a cut off disc on a dremel tool. I usually cut down the neck into the shoulder a little. Not to far or you will get less tention on the bullet. This allows the bullet to slide in and out of the neck. Now you can use which ever bullet you are working with. To get the right tention you might have to spend a couple of cases to get it just right. All my seating depths on my bolt action rifles are off the ojive and not the tip of the bullet. Thats not to say you shouldn't use that measurement especialy if your rifle uses a magazine or it is a level action because that measurement is important. The important thing is to make sure it will chamber into the action correctly. I use the Hornady bushing OAL gage that attachs to a set of digital calipers to measure the seating depth when setting up my seater die. It measures off the ojive and I can set the bullet off the lands what ever I need to.

    Hope this will help.