Values of hash marks for MP8

Discussion in 'Long Range Scopes and Other Optics' started by LRHWAL, Aug 16, 2007.

  1. LRHWAL

    LRHWAL Well-Known Member

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    IOR's manual says 1m at 1000m for both MP8 and mil dot. That's neither MOA or true mils last I did the maths. Does anyone know what the values are. I'll check it out at the range on the weekend, but am itchingto know in the meanwhile!

    Thanks.
     
  2. Jeff In TX

    Jeff In TX Well-Known Member

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    LRHWAL,

    The MP-8 reticle and mildot are the same except one uses hash marks the other uses footballs or round dots.

    I mil = 3.6" @ 100 yards or 36" (1 yard) @ 1000 yards.

    The nice feature with the MP-8 reticle is smaller hash marks at .5 mil.

    I was trained on mil-dots but like the hash marks better for ranging.

    If you want the formula for ranging with mil-dots shoot me an email or PM.

    Best of luck
     

  3. MachV

    MachV Well-Known Member

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    Jeffs right the IOR MP-8 is set up to be ½ mills at a cirtain setting...usualy 10x. Depending on the variable power and focal plain it could be MOA. If you can get to 18x?
    Take a yard stick to the range with ya and make sure it calibrates right and at what power.
     
  4. Jeff In TX

    Jeff In TX Well-Known Member

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    Sorry, this is not meant as a slam or to flame you but what is your statement getting at! Splain Lucy! You can't change from Mils to MOA because of the focal plane or power setting. Your reticle is calibrated for one or the other.

    Mils are Mils and Moa is Moa, they are totally different measurements, they aren't interchangeable and they don't change. 1 mil @ 100 yards is 3.6” and 1 MOA @ 100 yards is 1.047”. I don’t see any logic in your statement.

    If you want to measure the accuracy of your mil-dots, make a cross on a target or a sheet of the paper that is exactly 3.6" from the center of the cross to the end of each vertical and horizontal mark. Put the target at exactly 100 yards and verify the accuracy of your mil-dots or hash marks. If your reticle is in the second focal plane, turn your power ring until the first mil-dots cover all four marks. Mark your power ring so in the future you'll know where to turn it to for ranging.

    If your reticle is in the first focal plane, then verify the accuracy of the mil-dots or hash marks at all power ranges.
     
  5. MachV

    MachV Well-Known Member

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    It would be a great trick with a front focal plane, a fixed 16x or a scope that does not go to 18x. It is however posible and actualy quite easy to go from Mills to MOA with a 3-18,6-24 or 9-32 GenII mildot like the IOR MP-8. I have not tryed it yet but I'll bet the 9-36 set at 36 would actualy be ½ MOA hashes?
    I stumbled onto this neat little trick by acident as I sure aint smart enought to figure it out otherwise. There are those that can do the math and confirm it though :D

    Mark off 100 yards exactly,put a yardstick at one end and your second focal plane IOR scope with MP=8 reticle set at 18x at the other end.Now look through the dang thing and tell me how many inches it is between the hash marks :eek:
    Get back to me with what you find out :cool: I'll give you a hint it aint 3.6!
     
    Last edited: Aug 16, 2007
  6. SES50

    SES50 Well-Known Member

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    A while back I used Exbal to figure this out. The MP-8 Reticle is Mils at 10 power and MOA just under 18 power. I printed a grid pattern up at 1 inch squares and a grid pattern up at 3.6 inches but have not had a chance to take it out to the range to check it yet. But exbal says it should be something like 17.5 or 17.75 power for the MP-8 reticle to be equivalent to MOA.
     
  7. Jeff In TX

    Jeff In TX Well-Known Member

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    I'll agree with you that a second focal plane scope set at 18X isn't going to be 3.6" at 100 yards. More than likely that scope was calibrated for using the mil-dot reticle for ranging a given power setting such as 10X or some other value. That's why it's important to verify what the real power setting is if you're gonna use it for ranging. The factory mark on your power ring is one thing, but I've seen too many scopes where the factory marked setting was off. Any new scope we were given was always verified and more times than not we had to re-marked it. That's why for the longest time I was a fan of a 10X fixed power scope. Even to 1000 yards we didn't need more than that.

    Are you saying that at 18X the value between hash marks is 1.047 inches? In my head (ok a scratch piece of paper) I come up with roughly 1.58" at 18X or 1.51" at 17.5X. Now 14.2X would get you close to 1.047", if I'm following the logic here.

    Again trying not to flame you, just trying to understand the reasoning.
     
    Last edited: Aug 16, 2007
  8. MachV

    MachV Well-Known Member

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    I agree a guy should check to se at what power the reticle is calibrated at and yes it is a little different with all three 6-24s I have. Trying to figure out what power they where calibrated at is what led me to find the MOA thing.What I do is turn the power all the way up and dial it down till the hashes line up with the inch marks on the yardstick. I actualy set it so that 10.5" is the distance it takes 10 hash marks to cover and 21" for 20 hashes to get as close to MOA as posible? I found it is more acurate to turn all the way up and dial down to the new MOA calibration marks I put on the power adjuster.
    I dont pay any more atention to the power # than I do the range # on the side knob,near as I can tell they where just guessing and not very good at it! What matters is the power dial is turn to the calibration lines I put on it!
    18x + or - has ben working very well for shooting prairie dogs as mirage is ususaly too bad to use much more power than that anyway.
    I can see why someone who knows Mills would like them and I have to use them in the fixed 16Xs but MOA just works so much easier for me.
    As for helping with the reasoning I cant help...Note my signiture line,heck I'm just a reTIRED dairy farmer that welds mineing boxes for a liveing.
    If it works I run with,if it doesnt I mess with it till its FUBAR :D
     
    Last edited: Aug 16, 2007
  9. Chrismadrid

    Chrismadrid Well-Known Member

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    1) 1m at 1000m is EXACTLY 1/1000 of the radial distance or 1 mili-radian.

    2) On an SFP scope the reticle/image relationship quoted is only valid at one power setting - calibrating distances at other mag settings is JUST maths.

    On IOR scopes this "true" value differs scope to scope. It's marked on the zoom ring with a circle around the number. IIRC the new 4-28 for example is "true" at 14.

    3) Buy FFP! ;-)
     
  10. Jon A

    Jon A Well-Known Member

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    Jeff, the reticle is Mil calibrated at 10X. So at 18X each Mil marking would = 3.6" * 10 / 18 = 2.0" at 100 yds. Of course it also has 1/2 Mil hash marks which should be right around 1" at 100 yds. Plenty close enough for small holdovers/windage, etc.

    If you want to be more accurate, true MOA should occur somewhere between 17X and 18X and the only way to get that exact is to calibrate like MachV explained and mark it.

    Anyway, that should work nicely with that scope's MOA knobs. Though I agree with Chris--make it FFP with Mil knobs for me! ;)
     
  11. LRHWAL

    LRHWAL Well-Known Member

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    Oops....

    Don't know why I did it - maybe the metres that caught me.... I did the maths on MOA and wondered what they were thinking. You are of course all correct.

    I stick little luminous dots on a target at the right intervals at home and then check it out on the range. That's how I confirm.

    Most IOR's mil at 10X.

    Thanks for the replies.
     
  12. Jeff In TX

    Jeff In TX Well-Known Member

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    I'm following ya'll now. Sorry I've never been an moa guy except for measuring groups. I taught mils and it's simple enough now I can do it in my sleep.

    Plus in the Texas heat, best of luck doing any shooting beyond 500 yards with more than 14X power with the mirage. Actually 10X is about the best we can work with 1000 yards and 100+ degree heat.

    Good luck guys and thanks for making me see your light.
     
  13. overbore

    overbore Well-Known Member

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    Speaking of ranging---

    is there a list of typical animal heights for elk, Deer, Bear, coyote and antelope??

    Many thanks, Overbore
     
  14. SES50

    SES50 Well-Known Member

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    I have looked for this as well and have come up short. As I recall White tail and Mule deer are 18" from the top of the back to the bottom of the chest. I hunt black tail which are smaller and everytime I have shot one lately I mean to take some measurements but forget to do it. It would be great if there was a chart of measurements like they have for the human body in the sniper manuals.