Ballistic 'Whiz Wheel' solver

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by BryanLitz, Feb 3, 2011.

  1. BryanLitz

    BryanLitz <b>Official LRH Sponsor</b>

    Messages:
    633
    Joined:
    Mar 8, 2007
    I'd like to make everyone aware of a new ballistic solver called the 'Whiz Wheel':
    Accuracy 1st: Sniper Training & Products

    [​IMG]


    The Whiz Wheel is a non-electronic device that calculates ballistic solutions out to transonic range for any small arms bullet.

    Features include:
    *Density altitude calculator
    *Meters/MILS or Yards/MOA output
    *Trajectory prediction within 0.1 MIL or 0.25 MOA resolution
    *Wind deflection for any speed and direction
    *Spin drift
    *Leads for engaging moving targets
    *Corrections for inclined shooting
    *Ability to 'true' the solution for variations in MV or BC

    The tan colored sleeve is general, meaning it works with all wheels. The wheels are interchangeable laser engraved plastic that are custom made for your specific bullet, MV, sight height, and twist rate. Each wheel provides a full solution for a single round. Different wheels are required for each new round.

    Solving the wheel is very simple. Start by solving the density altitude (DA) with the small wheel, or getting it from a Kestrel. Then line up the DA with the range, and the wheel outputs drop. The drop can be corrected for incline via the table on the back of the sleeve. The back of the whiz wheel also calculates the lateral solution elements including wind, spin drift, and moving target leads.

    I was heavily involved in the development of this wheel and can vouch for the accuracy of the solutions which are generated with a point mass solver and measured G7 BC's. Furthermore I'll be available to answer questions about the whiz wheel on this thread.

    Contact for ordering the Ballistic Whiz Wheel can be found in the above linked website.

    -Bryan
     
  2. gbp

    gbp Well-Known Member

    Messages:
    227
    Joined:
    Aug 22, 2006
    OK, I'll bite and see where this takes us
     

  3. ericpetritz

    ericpetritz Well-Known Member

    Messages:
    53
    Joined:
    May 7, 2006
    This is interesting. It looks like you can get it with several "generic" wheels or it can be ordered with a custom wheel calibrate to one's exact setup? The idea of this seems excellent to me, no messing around with PDA's, dead batteries, etc. No electronics to break. With a custom wheel will this produce the same results for a given firing solution as your ballistic software? How quickly can the firing solution be determined? It seems like it would be faster than typing into a PDA.

    It is a little pricey but I may have to break down and try one...
     
  4. ericpetritz

    ericpetritz Well-Known Member

    Messages:
    53
    Joined:
    May 7, 2006
    A couple more questions:

    Can this be set up with drops corrected for scope adjustment errors?

    I assume it only is accurate to transonic ranges because it relies on density altitude instead of using temperature?
     
  5. BryanLitz

    BryanLitz <b>Official LRH Sponsor</b>

    Messages:
    633
    Joined:
    Mar 8, 2007
    A custom wheel can be produced according to your specific setup (bullet BC, velocity, sight height, etc). The solution is produced with a point mass solver, measured G7 BC's, and is accurate to within 1 click out to the range where the bullet slows to transonic speed.

    Errors in scope adjustment have to be corrected for outside this device; it outputs true MOA or MILS only.

    There is a learning curve, but once you've learned how to work with the device, it's quicker to get a basic solution than an electronic PDA. An exception might be if you're shooting at high angles. The correction for inclined shooting requires some mental interpolation.

    -Bryan
     
  6. ICANHITHIMMAN

    ICANHITHIMMAN Well-Known Member

    Messages:
    4,380
    Joined:
    Jan 31, 2008
    Cool my pdas keed croking anyhow and I refuse to pay 600+ for one of them high end units
     
  7. SBruce

    SBruce Well-Known Member

    Messages:
    1,786
    Joined:
    Oct 31, 2009
    Very Interesting,

    I will probably have to try one of these out!
    I am sure I'll have more questions later.

    Thanks for the info:)
     
  8. ericpetritz

    ericpetritz Well-Known Member

    Messages:
    53
    Joined:
    May 7, 2006
    To me the big selling point of something like this is the ability to get the same information normally provided by some type of mobile ballistic software but without the delicate electronics, battery life, etc. If it is not available with scope correction factors accounted for in the drop predictions, one is left to pack a calculator (I am not doing the math by hand in the field!) and the user is back to carrying an electronic device. Without being at all familiar with the software used in constructing these, it seems like it should be simple enough to add this at the customer's request. Maybe I am in the minority here, but I would find this much more useful with this built in.
     
  9. BryanLitz

    BryanLitz <b>Official LRH Sponsor</b>

    Messages:
    633
    Joined:
    Mar 8, 2007
    Eric,

    I totally agree with you.

    Instead of using a calculator to apply your scope correction factor to the solution, consider this:

    http://www.appliedballisticsllc.com/images/MATLAB.pdf

    It's a simple graph you can print out, laminate, and keep with the whiz wheel. The way it works is, you do your 'tall target test' to determine the actual reticle movement for a certain adjustment range, and you place a point on the graph. Then draw a line from the origin (lower left corner) to and thru your point using a straight-edge. In order to know how much 'actual reticle movement' you're getting for a given adjustment of your scope, just refer to the line that you drew.

    This card would be handy to have for your scope, even for use with other programs that don't allow a scope correction factor (not just the whiz wheel).

    It may someday be an option for a customer to specify his scope correction factor when having a custom wheel printed, but that is currently not possible.

    -Bryan
     
  10. chief71

    chief71 Member

    Messages:
    11
    Joined:
    Jan 18, 2012
    I've been using one of these for a little bit now and they work very well. I've also learned and have done the trueing for my rifle and load and I can tell you this device works very very well.

    Like Brayn mentioned there is a learning curve and I was fortunate enough to learn it from Robert at Accuracy 1st. Once that is understood and you can implement that new information it can easily replace your PDA/iphone software.

    Get it, learn it and you'll be happy with your fist round hits.

    R.
     
  11. Topshot

    Topshot Well-Known Member

    Messages:
    1,085
    Joined:
    Nov 3, 2008
    Bryan,
    Great idea. I would be very interested in the "Wheel" as a back up to my "Shooter" program. But I have a question on customizing the wheel to the desired G7 B.C.

    In particular I will be using the .338 Calibre Berger 300gn OTM Hybrid projectile. Now I have noticed in your book that the G7 B.C. below 2000 fps goes slightly up in value where as your derived G1 B.C. at 2000 fps takes a sudden dive downwards in value.

    I find this very strange!

    Now my testing has my data in perfect agreement with your G7 data to 2000 fps which is great, but from then on it is a closer match to your G1 B.C. data.
    So my question is can the wheel be custom made to variations in data?
     
  12. BryanLitz

    BryanLitz <b>Official LRH Sponsor</b>

    Messages:
    633
    Joined:
    Mar 8, 2007
    Topshot,

    It is possible to make a whiz wheel with a velocity banded BC (G1 or G7), if you provide your banded data.

    -Bryan