Whats a "true" Mildot? & Moldot measuring/zero charts

Discussion in 'Hunter (HFT) & Field Target (FT)' started by rubi-tong, Aug 1, 2009.

  1. rubi-tong

    rubi-tong Bernies MY *****

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    Just been reading the excellent thread on Range finding for HFT but I'm a little confused (Very easy, believe me) What is a true mildot?
    I thought ( and read) that a mildot is a representation of 36"@1000yds, The military say the average man is 6ft (below average for me, again:eek:) so if a man covers exactly 2mildots, then he's exactly 1000yds away.
    I use a computor program called Mil-Dot RangeFinder, you input a target size and the scope mag (10x in my case) and then drag the bottom of a circle (representing the target size) down a Mildot reticle, the top of the circle being fixed at the crosshair centre, watching the range window at the side, you can read what range the circle is covering in mildots.
    You can also input the MOA/DOT @10mag, I've always put in 3.6 but there's a button underneith saying "true Mildot", when pushed it changes the 3.6 to 3.438? So which is it 3.6 or 3.438??????
    Very confused:confused:

    If it matters any, im using a Falcon menace 10x42 MP20
     
  2. Ste Hughes

    Ste Hughes Daystate's whipping boy

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    its just the distance between the dots

    i think 3.44 MOA is true mildot size (from memory)

    :cool:
     
  3. martin c

    martin c New Member

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    mil-dot

    mil-dot is derived from the metric system of angular measerment now used by hm forces-: hope these definations help
    1 milliradian - a unit of angular distance equal to one thousandth of a radian
    angular unit - a unit of measurement for angles
    microradian - a unit of angular distance equal to one thousandth of a milliradian
    radian, rad - the unit of plane angle adopted under the Systeme d'Unites; equal to the angle at the center of a circle subtended by an arc equal in length to the radius (approximately 57.295 degrees)


    2 The Mil-dot reticle was originally developed for the millitary for range-finding purposes. Each dot on the Mil-dot reticle represents 3.6 inches at 100 yards or 36 inches at 1,000 yards. Although these ranges are well outside the ability of most airguns, the distances can be scaled down to provide a very effective reticle for airgun use. Many airgunners swear by the Mil-dot reticle and through experience have developed a natural understanding of what each dot represents at a given range. :eek:
     
  4. rubi-tong

    rubi-tong Bernies MY *****

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    Are, I see:confused:
    Thanks for the info :eek:
     
  5. Brian.Samson

    Brian.Samson Allowed in Sales Staff Member

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    I did a bit of research on this a few years ago now and from memory I managed to find 4 different definitions of what a "MilDot" is.

    Don't worry too much about it though, the definition I use as being true is the distance between the centre of one dot to the centre of the next dot is 1 MilliRadian or 3.44 MOA (It's not the distance between the dots, that's usually 0.8 MilliRadians.

    Your Falcon also uses the 3.44 MOA definition of a MilDot so I would consider that to be "True"

    Ok you don't really care about any of that though, you just want to know how to use them for your holdovers and possibly for rangefinding.

    Chairgun will get you in the right ballpark, but I prefer to trust bits of paper... to that end I knocked up some extremely nerdy practice targets.

    These targets need to be placed out at the correct printed range because they are graduated with Mildots at the correct size for that range.

    12 Yards
    13 Yards
    15 Yards
    20 Yards
    25 Yards
    30 Yards
    32 Yards
    35 Yards
    40 Yards
    42 Yards
    45 Yards

    Note: These targets have been updated now - the latest versions can be found at www.anstonftc.co.uk/targets

    Print those out, place them out at the correct measured distance and look through your scope to check that the mildots on the targets line up exactly with your scope.. if they don't something's wrong - also check that the 150mm marking on the targets measures 150mm - if it doesn't then you may need to adjust the Print settings in Acrobat to produce a 100% print and not "Print to Fit paper".

    Once they all line up, shoot groups at each distance by aiming your crosshairs at the centre of each target (the Red Dot) - you'll then be able to inspect the targets to see exactly what your holdover or holdunder is for each range - for added accuracy, make sure your crosshairs are level when you shoot. i.e. don't "cant" your gun or the results will be slightly wrong.

    For example if you put the 40 yard target out and find that your pellets are all landing on the half mildot mark, then that's your holdover for 40 yards - 0.5 mildots. There's no need to measure anything and then convert to mildots, it's all done for you with the exactly sized mildot graduations on each target.

    There are also a selection of killzones on each target for you to practice on - the smallest killzone on each target is the smallest killzone allowed in HFT at that distance.
     
    Last edited: May 11, 2012
  6. Mog

    Mog New Member

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    You really are a top man for giving all this help, well done and thank you. :)
     
  7. Kingplinker

    Kingplinker " Horsham HFT champion 2010 "... apparently...

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    No use to me but I agree Charles , it's good to see people sharing otherwise ' secretive ' HFT techniques with the rest of the members here . Excellent . :)

    Dave
     
  8. RobF

    RobF Administrator Staff Member

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    Top stuff Brian !... another sticky made :)
     
  9. JEV

    JEV Member

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    True Mil Dot is 100mm at 100m. this the reduces in proportion i.e. 50mm at 50m 25mm at 25m etc. etc. Th scope maker should state the mag at which mil dots are 'true'. On some makes including Bushnells the mag at which the Mil Dot is 'true' is marked in a different colour.
     
  10. Adam

    Adam Active Member

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    It's just a measure of "1 in a thousand". Or put another way, the distance between the centres of two adjacent mildots is one thousandth of the distance of whatever you're aiming at.

    Hence 36" at 1000 yds is a true mildot because 36" is one yard: 1 yard at 1000 yards.
    Likewise 1 metre at 1000 metres is a true mildot.

    Mildots apply to both metric and imperial measurements, or any form of measurements, but because metric uses multiples of 1000 it makes the calculations easier. 1 mildot is 40mm at 40m because there are 1000 mm in 1 metre.

    If you work out what the actual angle of a mildot is, it is 0.0573 degrees. MOA (minutes of arc) are 1/60th of a degree so this works out at 3.44 MOA.

    So 36" at 1000 yds is "true", 1m at 1000m is "true", and 3.44 MOA is also "true" (or 3.438 rounded to 3 places instead of 2).

    A mildot is not exactly the same as a milliradian but I'm really really not ready to go into the difference! :eek:
     
  11. Brian.Samson

    Brian.Samson Allowed in Sales Staff Member

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    What's the difference between a "mildot" and a "true mildot" though :D
     
  12. martin c

    martin c New Member

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    true or not

    radian's are a measure of angle , as said before and are basically a metric replacement for the old degree's ,minute's and second's system that most people still use .

    the mildot is based on this system and has been said in previous posts a factor of 1-1000 is a true mildot
    however as most people still use imperial then the midot has been adopted to work within this system also.

    so true mildot is purely metric where as if used with yard's or inch's then it can not be a true mildot.

    err hope this helps :confused::confused:

    ps lets not forget that a metre is 3 inches longer than a yard
     
    Last edited: Oct 6, 2009
  13. Brian.Samson

    Brian.Samson Allowed in Sales Staff Member

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    Almost... :)

    Mildots aren't purelly metric and it's not true to say "if used with yards or inches then it cannot be a true mildot" - a 3.6 inch object at 100 yards is very very close to being exactly 1 milliradian.

    A true trigonometric milliradian is what I take to be a true mildot (actually it's not quite 1:1000, but it's very very very close - a 1m object at 1000m is actually 1.000000333 milli radians - it's the difference between the length of the arc and the length of the straight line)

    NATO, the former Soviet Union, Finland and Sweden all used to have slightly different definitions of the measurement of a mildot - none of them were true trigonometric definitions.

    But... none of that matters for airgun ranges - any mildot definition will be close enough so long as you know the magnification on your scope where the mildots are "true" - and true can be whatever definition of a mildot you care to run with :- NATO, Trigonometric, Russia/Finland, Sweden
     
  14. martin c

    martin c New Member

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    omg

    i accept all that mate and i think we should all leave it there before we all disappear up our own , well you know what i mean

    all the best, now if you dont mind i think i need a lay down after reading your post :D:D:D:D:D:D:D:D:D:D
     
    Last edited: Oct 6, 2009
  15. Brian.Samson

    Brian.Samson Allowed in Sales Staff Member

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    Yeah, I sort of set you up with the question "what's the difference between a mildot and a true mildot" :D - I wasn't having a pop at you, I just find it quite amusing that out of all the definitions out there of what a true mildot actually is - none of them are completely accurate.

    The term "true mildot" was probably the brainchild of someone working in marketing trying to sell more scopes.

    It really doesn't matter though - who cares :D
     
  16. Tallycat

    Tallycat New Member

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    True mil dot

    Really helpful info, but try as I might I cannot print these targets off measuring 150mm - they print off measuring 151.5mm? Will this make much difference?
     
  17. Brian.Samson

    Brian.Samson Allowed in Sales Staff Member

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    That's fine - In fact I think from memory the lines are 150mm between the two vertical lines, so if you're measuring to the outsides of the lines it could very well be 151.5

    So long as it's near enough, that's fine though.
     
  18. Tallycat

    Tallycat New Member

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    Thanks, I was measuring from inside the lines... I didn't think 1.5mm @ 12, 25, or 40 yds etc. would make a difference, but thought I'd ask. Now time for practice :D
     
  19. PeteM

    PeteM New Member

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    Full Explanation of MILDOTS

    THE ATTACHED PDF GIVES A FULL EXPLANATION OF MILDOTS.
    Hope you find it useful.
     

    Attached Files:

  20. Tench

    Tench WHFTA World Champion 2016.

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    If a scope is "true mildot" then 1 dot is 1" at 27.777 yards, (100/3.6) to enable more accurate prediction of mildots in respect of trajectory when using CG etc i have measured my own scope against a ruler, i found that my scope is giving me 1" per dot at 30 yards, 6 dots span 6" at this distance when on maximum mag, 10x, adjusting the magnification in CG tells me that my scope if it is true mildot is working at a magnifcation of 10.8, the mag is irrelavent, what is more important is the fact that the program is now calibrated to my scopes settings so it is displaying what i should be getting on the range.

    Cheers Simon.
     

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