New "true" time of flight device. What do you all think?

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by Michael Eichele, Apr 9, 2009.

  1. Michael Eichele

    Michael Eichele Well-Known Member

    Messages:
    3,829
    Joined:
    Jan 6, 2003
    To all,

    I am currently working on a device that will give a shooter the real time of flight of his bullets. This device will NOT calculate TOF rather it gives real time results. It will require a shooter to take a laptop to the range. It would also be able to be used from 0-1000 yards as well as 0-100 yards, 100-200 yards, 200-300 yards, 300-400 yards ect... for modeling purposes.

    This device will NOT calculate BC's ect....All it will do is give you the real TOF so that you can decide what to do with the information. You would have to also be shooting over a chrony to get an accurate velocity to go with that TOF and you would need a pocket weather station. Later in the advanced stages, there may be velocity and atmosheric data included in the software and device, but for now it is just TOF.

    The catch is that it is fairly expensive to manufacture. It will cost me nearly 1K to put a unit together for up to 1000 yards. A bit less for less yardage and a bit more for more yardage.

    Now my question to all of you is (and I am sure only a few of you would be interested in owning a unit) how many of you would be interested in renting a unit? I would have to work out the details on how to secure a deposit and legnth of time used etc.....

    It would be an economical, accurate and simple way to determine an accurate BC for your bullets.

    Oehler no longer produces the 43 which was based on a similar principal to what I am cooking up. They stated to me that the cost and time wasnt worth the amount of interest. My thought is that if someone offered a unit they can rent at a reasonable rate for a reasonable amount of time, there may be more interest.

    What do you think.

    Any opinions here are welcome.
     
  2. jwp475

    jwp475 Well-Known Member

    Messages:
    2,595
    Joined:
    Feb 4, 2005
    Can you make an acustical target that will attach to the Oelher 43? Can you make this device attach to the Oelher 43?

    I am interested in something like that
     

  3. WildcatB

    WildcatB Well-Known Member

    Messages:
    461
    Joined:
    Jan 27, 2008
  4. Michael Eichele

    Michael Eichele Well-Known Member

    Messages:
    3,829
    Joined:
    Jan 6, 2003

    It wouldnt interface with the 43.
     
  5. Michael Eichele

    Michael Eichele Well-Known Member

    Messages:
    3,829
    Joined:
    Jan 6, 2003
    Thank you for the link.

    Yes it would be very similar to that. Minus the I beams. this method would either use noise as in the super sonic crack to stop the clock or it would use a pressure activated switch upon impacting a large target. The activation switch would be an acoustic device within 10' of the muzzle. The math within the program would correct for any distance figures.
     
  6. Michael Eichele

    Michael Eichele Well-Known Member

    Messages:
    3,829
    Joined:
    Jan 6, 2003
    After re-reading the link, I suspect that the device I am working on would offer a much smaller margin of error. This is due to the fact that there will be an actual cable between the Laptop and the noise sensors or pressure switch. It is easy to calculate the time it takes for the signal to reach the PC to stop the clock, which isnt much to begin with. Much easier than trying to factor the current speed of sound.
     
  7. jwp475

    jwp475 Well-Known Member

    Messages:
    2,595
    Joined:
    Feb 4, 2005
    Could you make one that would?
     
  8. Michael Eichele

    Michael Eichele Well-Known Member

    Messages:
    3,829
    Joined:
    Jan 6, 2003
    I am not sure. I dont own one and dont know how they work. I am sure anything is possible but without first hand knowledge, I cant say for sure.

    If you would give me some insight on how the system works, then I maybe able to help you.
     
  9. jwp475

    jwp475 Well-Known Member

    Messages:
    2,595
    Joined:
    Feb 4, 2005
    If you would be interested in working on one for the Model 43 I could send the 43 to you.
     
  10. Michael Eichele

    Michael Eichele Well-Known Member

    Messages:
    3,829
    Joined:
    Jan 6, 2003

    Before you do that can you tell me any technical info on it? What will it do that it would work with my devices?

    I guess what I am trying to get at is how will my devices help the 43?
     
  11. jwp475

    jwp475 Well-Known Member

    Messages:
    2,595
    Joined:
    Feb 4, 2005
    Oelher made Acustical targets for the model 43, the one that I purchased does not have the acustical targets, it has every thing else. I just purchased this one and I am not famillar with it at this tim, but I would like to have acustcal target to test bullets for true BC
     
  12. BryanLitz

    BryanLitz <b>Official LRH Sponsor</b>

    Messages:
    633
    Joined:
    Mar 8, 2007
    Michael,
    On the business end...
    Your idea may be very timely. The fact that Oehler is withdrawing from the market means there will be a void for the high end ballistic lab equipment available to the average shooter. I don't know the full extent of your ambition with this project, but maybe you can fill that void. Last I knew, the Oehler business was up for sale. I would highly recommend getting in touch with Ken. I'm sure he's got the answers to your questions about the market for such tools and LOADS of other valuable information for you.

    On the technical side...
    You mentioned 1000 yard capability with a wired system. Dealing with 1000 yards of coax is challenging at best, and downright impossible over some terrain. In addition to that, I think the reason why the Oehler system only goes to 300 meters is because that's as far as a signal can be reliably transmitted thru coax (with practical power supplies) without needing to be amplified. Amplification adds another component and level of complexity to the system.
    I'm certainly not discouraging your effort to develop such a system. I just want to illuminate some of the challenges of a wired apporach.
    When developing my own system, I almost decided to use wires, but went wireless in the end. It just makes it so much easier and more flexible to set up and you can easily find transmitters that work well over 1000 yards.

    It would do loads of good for the LR shooting sports to have a systematic way for shooters to accurately measure BC's over long distance.

    Good luck,
    -Bryan