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Newb ? Case gage, caliper, or both

Discussion in 'Reloading' started by mdpbowtech, Oct 31, 2012.

  1. mdpbowtech


    Dec 10, 2011
    Total newb here as I just ordered a turret press a few days ago. I have been reading a lot on the forums and was curious if I could just use a 9mm case gage instead of using a caliper? I have not bought either one yet so was wondering if I needed both. I am only reloading 9mm and its just for range use out of my glock 19 if that matters.
  2. F106 Fan

    F106 Fan

    Oct 19, 2011
    You absolutely need a set of calipers to measure OAL. A case gauge will only measure against SAAMI Max OAL which is 1.169". I'm not even sure that all case gauges do this.

    Basically, the case gauge is for checking case length from the case mouth to the case head and for checking diameter.

    You don't absolutely need a case gauge because you can use the chamber of your Glock to do the same thing. Just remove the barrel from the gun, 'kerplunk' the round into the chamber and see that it fits. Now, rotate the round and make sure it drags only on the case mouth. The bullet should not touch the rifling - and it won't even come close in most cases.

    It is likely that the Glock chamber is looser than a case gauge. You would be better served by doing both. Check dimensions with a case gauge and test functionality with a 'kerplunk' test.

    I have both calipers and a case gauge for everything I reload. The rifle gauges check every dimension of the case but don't measure bullet dimensions or OAL.

    Last edited: Oct 31, 2012

  3. fredj338


    Dec 22, 2004
    You do NOT need a case gage, you must have calipers. The case gage tells you nothing your own bbl won't. Case gages do NOT meadsure correct OAL, your bbl does. They are a convenience in checking for proper crimp & sizing, or finding an error in a seated bullet. I reloaded for 30yrs before getting case gages. They are a must for semiauto rifle rounds in setting the dies up, but not a big deal for handguns rounds IMO.
  4. noylj


    Jul 20, 2010
    Case gage is almost a total waste of money, but it makes people feel better. Your barrel or cylinder is your perfect case gage.
    You do need a caliper. You can use a micrometer also, but it really is not needed.
    I have reloaded for 40 years and NEVER needed or wanted a case gage--NEVER EVER at any time.
    I have ten different 9x19 guns and all but ONE BHP are happy with the COL that any other gun finds acceptable. Some tend to like a little longer or shorter COL, but that is a degree of fine-tuning that few worry about.
    For .223, you should get an attachment for your calipers to measure COL (not OAL) by bullet ogive and not the tip that can be damaged and varies quite a bit any way.
  5. Kwesi


    Sep 23, 2006
    I need the case gauge because I shoot a SBR so not as convenient to check the rounds as on a pistol barrel. I've been finding a small amount of 9mm rounds that will not case gauge due to a bulge ( range pick up brass ).
  6. Three-Five-Seven

    Three-Five-Seven Señor Mombo Millennium Member

    Aug 8, 1999
    Great Southwest
    I find the Dillon Six Hole case guages to be convenient, fast, and reliable. YMMV.
  7. F106 Fan

    F106 Fan

    Oct 19, 2011
    It is certainly possible to make the case that a gauge is not required. However...

    I would still find it more convenient to have a case gauge laying on the bench rather than having to disassembly a gun all the time.

    And then there is the matter of WHICH gun to disassemble. My .45 ACPs have to fit a Glock, a Sig 1911 and a couple of stock Colts (one is a Gold Cup) plus another Colt with a Barstow barrel. I guess I could try to figure out which had the smallest chamber but why bother? The case gauge is laying right there on the bench.

    But, no, you don't absolutely need one.

  8. noylj


    Jul 20, 2010
    Just saying--40 years of reloading and never needed and never wanted. About 5-10k rounds a year for 40 years.
    Run all your 9x19 range pick-up (now that some people like to shoot 9mm Major and leave the cases at the range) through a Lee Bulge Buster and 9mm Mak FCD and eliminate the bulges before you even start to reload.
    I have NEVER had a problem with rounds not chambering for 37 years, then I started hitting 9x19 range pick-up that formed a raised ridge (see Lee Bulge Buster ad for exact picture) and didn't notice and had a round stick in one of my P08s. Bugger to disassemble, but toggle and my arthritis meant I couldn't open the toggle link by hand.
    Since Lee came out with the 9mm Mak FCD, I have not had that problem again.
    Case gage--use 'em if you got 'em, but all they will tell you is to look at your loading set-up because there are problems (and the barrel and cylinder in NOT that difficult to remove and use from almost any normal handgun). When you fail a case gage, do you determine the cause and eliminate it?
    In other words, is it a tool or a crutch?
  9. DWARREN123

    DWARREN123 Grumpy Old Guy

    Jan 25, 2008
    Clarksville, Tn.
    Calipers, use the chamber as a size gauge. Round should just go in/out of chamber on its on.
    Make sure rounds fit/feed from mag.
    Last edited: Nov 1, 2012
  10. superhornet


    Apr 1, 2005
    Calibers--and I convert inches to mm for AOL. Much easier to me to get it down to a very fine line. I build a chart with all the different cartridges I load with the bullet and mm data.
  11. unclebob


    Oct 14, 2000
    Mary Esther FL
    Between calipers and case gauge the calipers are more important. But the case gauge makes it a lot easier in setting up the reloading dies. It also helps in case gauge ammo when you have more than one gun of the same caliber. For me it is both.
  12. Boxerglocker

    Boxerglocker Jacks #1 Fan

    Mar 6, 2003
    Lynnwood, WA
    Calipers at bare minimum, case gauges are nice to have for quick go no go assessments. The Dillon ones are particular useful for rifle, I use the mine every time I prep brass.
    I load up to 2K of 9mm a month and admitted don't case gauge all of it these days. However always gauge match ammo (rifle and pistol) and the EGW 6 hole case gauge makes short work of it.
    Single case gauges a cheap and handy to have on the bench (No need to tear your pistol down) especially if you have to troubleshoot issues with setting up dies and your loading process.
  13. Three-Five-Seven

    Three-Five-Seven Señor Mombo Millennium Member

    Aug 8, 1999
    Great Southwest
    There is no way I'm going into a $1000 weekend without checking my loads in a case gauge or chamber. To loose a big match because a faulty round was not detected before hand is inexcusable. On the rare occasion that I use factory rounds in a big match, those get checked too.
  14. sig357fan


    Apr 8, 2008
    SW OH
    Case gauge does one thing, gauge cases.

    Calipers do several things; measure COL, case length, bullet dia., etc.

    If I was getting both, I'd get the calipers first.

  15. Boxerglocker

    Boxerglocker Jacks #1 Fan

    Mar 6, 2003
    Lynnwood, WA
    That's exactly what I have experienced and posted in the past. Buying a $10-15 case gauge or blow a $1000 match weekend for a 14 cent round you failed to check.
  16. M24C


    Oct 31, 2002
    Calipers are a must! I have 3 of them. The case gauge is a convenient tool for me, depending on what the loads are for. I have found if the cartridge fits the gauge it fits my barrel, and if I want to know that I measure them in the gauge. Even self defense factory loads. Like others have said for a match, it would have to pass through a gauge before I would trust it.

    posted using Outdoor Hub Campfire
  17. ADK_40GLKr

    ADK_40GLKr Adirondacker with a Glock

    Nov 14, 2010
    RFD NY Adks
    My Lee press has a sizing die, so it pretty well fixes diameter.

    I DO need Calipers for OAL. I had a couple GAP rounds get stuck in the magazine because some of my first reloads were too long.

    I check OAL frequently, now!
  18. F106 Fan

    F106 Fan

    Oct 19, 2011
    Everybody has a sizing die that sets case diameter. Yet many of us have case gauges and others check the loaded rounds in their chambers. Some use both...

    There is the possibility that a bullet diameter is too large and the assembled round won't clear the gauge. There is also the possibility that the taper crimp isn't quite closing the case mouth.

    Some people have been known to not properly adjust the sizing die.

    It's just a Quality Assurance kind of thing and is particularly important among competitors. Having any kind of ammo failure just about guarantees the shooter will be out of the running for any awards.