Chrony draws a blank

Discussion in 'Equipment Discussions' started by goose, Aug 11, 2009.

  1. goose

    goose Well-Known Member

    Messages:
    190
    Joined:
    Dec 26, 2008
    I got a new chronograph last winter and have used it about 5 times. I believe it's a comp electronics model. The first time I used it I had to move it around several times to get a reading. The next 3 times I used it it worked every time. Tonight I fired seven rounds with none of them registering. I moved it up and down, made sure it was centered and it was placed about 5 feet past the muzzle. It was a bright clear day, but it was early evening with a couple hours of light left. I tried turning it on and off, taking out the battery. How sensative are they to light conditions and positioning? Any other things to check?
     
  2. learning

    learning Well-Known Member

    Messages:
    208
    Joined:
    Apr 24, 2009
    Five feet is probably to close. The muzzle blast is probably moving it way to much. I have knocked mine over from having it to close.
     

  3. goose

    goose Well-Known Member

    Messages:
    190
    Joined:
    Dec 26, 2008
    Thanks, I was able to find in the manual for rifles they recomend 10-15 feet.
     
  4. learning

    learning Well-Known Member

    Messages:
    208
    Joined:
    Apr 24, 2009
    If it does not have a break you might be better off at 15' if it has a break you should be able to bring it in a little.
     
  5. LRHWAL

    LRHWAL Well-Known Member

    Messages:
    422
    Joined:
    Jan 11, 2006
    I'm not sure how the unit looks - i.e. screens and leads to a unit or screens with integral unit.

    I need to put my unit right back at my shoulder to get a good reading otherwise the blast, even if it's behind the muzzle, can affect it.

    So screens way up front, unit right back at your shoulder. I also sometimes shield it by popping it in the rifle case with the lid half closed. Seems to work better.
     
  6. jmason

    jmason Well-Known Member

    Messages:
    1,527
    Joined:
    Feb 6, 2008
    Muzzle blast and bright sun will kill your chrony every time. If it's really bright out the sky screens won't be any help unless the shade is cast directly over the sensors. Also they don't like low light before it gets dark out. They are very sensitive.
     
  7. JARHEAD1371

    JARHEAD1371 Well-Known Member

    Messages:
    676
    Joined:
    Oct 9, 2008
    Same thing has happed to me before. My chrony wouldn't read shots that were fired too early. Also if it's too clouldy that has effects on accuracy of the speed the chrony reads.
     
  8. Chief1942

    Chief1942 Well-Known Member

    Messages:
    62
    Joined:
    Jun 3, 2009
    Right here in this one thread is the major reason I hesitate even purchasing a chrongraph. They don't like the sun, they don't like the clouds, they hate muzzle blast, and even if they have everything to their liking, they still will produce error factors as much as 8%. So what is the purpose of even doing this if one cannot rely on the accuracy of the equipment? I sense I would be better off not even worrying about MV and just develop a drop chart for my loads in my rifle at the yardages I will be shooting. Of course doing this will result in a cost in ammunition equaling the cost of a good chronograph. Just ain't no inexpensive way to merge into this undertaking I guess. :cool:
     
  9. 30-338

    30-338 Well-Known Member

    Messages:
    214
    Joined:
    Jan 25, 2008
    Good point but you still would have to reshoot your drops with every change of powder or other components. I find them extremely valuable but they have made me so mad I could spit when they fail and I have scheduled a day at the range to do load development,,,very frustrating! I was happy with the PVM-21 for a while and then it started to malfunction..( inadequate connections for field use I think????).so I think my next will be the CED Milleniun II with the infra red attachment ( which purportedly does away with the need for ambient light) but then you need a power source or must hassle batteries, etc. I regard them as necessary evils but worth it to do load development and for external ballistic calcs 30-338