6MM Ballistics

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by dbhostler, Oct 16, 2003.

  1. dbhostler

    dbhostler Well-Known Member

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    It's a bit much to ask, but would someone run the numbers on a 107gr Sierra MK out to 1K at 3100fps. I was just curious of what the trajectory would be. The rangemaster said 53" at 200yds would put me on paper at 1K.
    Thanks,
    db
     
  2. a.JR

    a.JR Well-Known Member

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    Db,If it's a true 3100fps your come up will be approx 18 to 20 minutes from 100 to a 1000 yds,target is 2 minutes from centre X to target edge so this will get you on paper..Jr..Jeff Rogers
     

  3. Len Backus

    Len Backus Administrator Staff Member

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    Isn't it amazing that the answer can come so easily from halfway around the world? [​IMG]
     
  4. Darryl Cassel

    Darryl Cassel Well-Known Member

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    dbhostler

    With that bullet having a BC of .555 and with a speed of 3100 FPS, you will need 27.4 MOA to reach the 1000 yard mark.

    If you set your scope so the bullets are printing 27 1/2" high at 100 yards, you will be on target at 1000 yards.

    That's at 1000 feet elevation and 50 degree temps.

    DC [​IMG]

    [ 10-16-2003: Message edited by: Darryl Cassel ]
     
  5. dbhostler

    dbhostler Well-Known Member

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    Jeff, Len, Darryl;

    Thanks for your replies, I didn't have a chance to check where the rifle was printing with the scope at zero elevation, but my final up was 23.5 minutes. I'll have to print this at 100. It should be about 4" high, right Darryl?
    How much above the line of sight would the bullet be at its higest trajectory?

    db
     
  6. 700

    700 Well-Known Member

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    DB
    Given a 1000 yard zero, higest trajectory will be at 557 yards with a height of 87.5 Inches, 15.01MOA.

    I got 24.05 MOA as the approx come up to go from 100 yards to 1000 yards.

    Rgds

    700
     
  7. Darryl Cassel

    Darryl Cassel Well-Known Member

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    DB

    I sent you the drops for 1100 yards for that bullet and velocity and not for 1000 yards..

    I just went back to the Oehler program and got the correct info for you.

    With a Velocity of 3100 and using the Sierra 107 Gr with a BC of .555 here is what you need for placing that bullet on target at 1000 yards.

    You will need 23 MOA from a 100 yard zero.
    That means if you click the scope so it is printing 23" high at 100 yards, you will be on target at 1000 yards.

    At midrange the bullet at it's highest arc (bullet path from a 100 yard zero) is 241.14" above the line of sight.

    Sorry I droped down to the 1100 yard info to come up with the 27 MOA I first posted.

    Later
    DC
     
  8. dbhostler

    dbhostler Well-Known Member

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    Thanks again fellas. Your programs are truly amazing. Too bad they won't let us shoot a few tracer rounds at the range. You could appreciate the word trajectory a little more.
    Could you recommend a program I could download in my computer that would make this information available?
    db
     
  9. a.JR

    a.JR Well-Known Member

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    Db....Sorry mate i gave you a bumm steer as well ....I don't have a program but i shoot 1K regularly on my range....It's hot and humid and at sea level so my figures come from here only....My pal shoots a 6BR at 2920fps and the come up is 27.5 minutes,my lightgun is a 6mm x 55 imp and it shoots the same 107smk at 3375 fps ,the come up on it is 16 minutes exact..JR..Jeff rogers
     
  10. dbhostler

    dbhostler Well-Known Member

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    No problem Jeff, it's always good to hear from you "down under", g'day. [​IMG]
    db
     
  11. sscoyote

    sscoyote Well-Known Member

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    Say Mr. Jeff, you say you're getting 3300+ f.p.s. out of that big Sierra from that 6.5X55 necked down and blown out?? Man that sounds better than the .284 case. Does the 6.5X55 have a larger capacity than the .284??

    [ 10-24-2003: Message edited by: sscoyote ]
     
  12. a.JR

    a.JR Well-Known Member

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    SS,yes the cartridge is actually a 6BR +600 thou.....The 6BR is 1.560 and the Swede is 2.160 ,using A Competition 6BR reamer and plungeing it in a further 600 thou it becomes the right dia for the Lapua 6.5X55 brass at .479 ......My load is quite high in the pressure so tread carefully...I load 47.5 gns of Hh4350 for 3375 fps ,next most successfull is 52gns of VV560 at same speed......Capacity is 60 gns of water when full and is smaller than the 6X284..JR..Jeff Rogers