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Help! need calcs!

gunnut505gunnut505 Member Posts: 10,290 ✭
edited June 2006 in Perry Shooter Competition Shooting and Reloading Forum
Just got drawn for public land antelope after 10 years of applying/getting turned down, and need someone to run this stuff for me to verify what my Oehler said as it died on me.

I'm running a Sierra #2140 165HPBT Gameking over 76.4gr. of Reloader22 for a velocity of 3100fps, and energy of 3520.
With a 225yd. ZERO, and the line-of-sight being 1.75" above the bore, through a 26" tube; what would be my drops in inches at 350yds, 425yds, and 550yds?

OK, now same question with same bullet, but using 79.5gr. of H4831 for a velocity of 3150 and energy at 3600?

Thanks!
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  • walliewallie Member Posts: 8,595 ✭✭✭
    edited November -1
    ttt.jpg
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  • JustCJustC Member Posts: 16,056 ✭✭✭
    edited November -1
    Calculated Table
    Range Drop Drop Windage Windage Velocity Mach Energy Time Lead Lead
    (yds) (in) (moa) (in) (moa) (ft/s) (none) (ftlbs) (s) (in) (moa)
    100 1.8 1.7 0.8 0.8 2838.4 2.542 2951.2 0.101 17.8 17.0
    125 2.0 1.5 1.3 1.0 2773.3 2.484 2817.3 0.128 22.5 17.2
    150 2.0 1.3 1.8 1.2 2709.1 2.426 2688.4 0.155 27.3 17.4
    175 1.6 0.9 2.5 1.4 2645.8 2.370 2564.3 0.183 32.2 17.6
    200 1.0 0.5 3.3 1.6 2583.5 2.314 2444.9 0.212 37.3 17.8
    225 -0.0 -0.0 4.2 1.8 2522.0 2.259 2329.9 0.241 42.4 18.0
    250 -1.3 -0.5 5.3 2.0 2461.3 2.205 2219.1 0.271 47.7 18.2
    275 -3.0 -1.0 6.5 2.2 2401.5 2.151 2112.6 0.302 53.2 18.5
    300 -5.0 -1.6 7.8 2.5 2342.5 2.098 2010.0 0.334 58.7 18.7
    325 -7.5 -2.2 9.3 2.7 2284.3 2.046 1911.4 0.366 64.4 18.9
    350 -10.4 -2.8 10.9 3.0 2226.9 1.995 1816.5 0.399 70.3 19.2
    375 -13.7 -3.5 12.6 3.2 2170.3 1.944 1725.3 0.434 76.3 19.4
    400 -17.4 -4.2 14.5 3.5 2114.5 1.894 1637.8 0.469 82.5 19.7
    425 -21.7 -4.9 16.6 3.7 2059.5 1.845 1553.7 0.504 88.8 20.0
    450 -26.4 -5.6 18.9 4.0 2005.4 1.796 1473.1 0.541 95.3 20.2
    475 -31.8 -6.4 21.3 4.3 1952.1 1.748 1395.9 0.579 102.0 20.5
    500 -37.6 -7.2 23.9 4.6 1899.7 1.702 1322.0 0.618 108.8 20.8
    525 -44.1 -8.0 26.7 4.9 1848.2 1.655 1251.3 0.658 115.9 21.1
    550 -51.2 -8.9 29.7 5.2 1797.7 1.610 1183.8 0.699 123.1 21.4
    575 -59.0 -9.8 32.9 5.5 1748.2 1.566 1119.5 0.742 130.5 21.7
    600 -67.5 -10.7 36.3 5.8 1699.7 1.522 1058.2 0.785 138.2 22.0

    26 Jun 2006 17:02:41, JBM [http://www.eskimo.com/~jbm]

    this is with a book est for the 165gr HPBT BC above 2600FPS to be .363



    I figure the bullet in flight at 3000+ fps should be a bit closer to .400 BC, so here is another chart reflecting that interpolation

    Calculated Table
    Range Drop Drop Windage Windage Velocity Mach Energy Time Lead Lead
    (yds) (in) (moa) (in) (moa) (ft/s) (none) (ftlbs) (s) (in) (moa)
    100 1.7 1.6 0.7 0.7 2861.9 2.563 3000.4 0.101 17.7 16.9
    125 2.0 1.5 1.1 0.9 2802.5 2.510 2877.0 0.127 22.4 17.1
    150 1.9 1.2 1.6 1.0 2743.8 2.458 2757.8 0.154 27.1 17.3
    175 1.6 0.9 2.3 1.2 2685.9 2.406 2642.6 0.182 32.0 17.5
    200 0.9 0.5 3.0 1.4 2628.8 2.355 2531.4 0.210 37.0 17.6
    225 -0.0 -0.0 3.8 1.6 2572.4 2.304 2423.9 0.239 42.0 17.8
    250 -1.3 -0.5 4.8 1.8 2516.6 2.254 2320.0 0.268 47.2 18.0
    275 -2.9 -1.0 5.8 2.0 2461.6 2.205 2219.7 0.298 52.5 18.2
    300 -4.9 -1.6 7.0 2.2 2407.3 2.156 2122.8 0.329 57.9 18.4
    325 -7.2 -2.1 8.3 2.4 2353.6 2.108 2029.2 0.361 63.5 18.7
    350 -10.0 -2.7 9.7 2.7 2300.6 2.061 1938.9 0.393 69.2 18.9
    375 -13.1 -3.3 11.3 2.9 2248.3 2.014 1851.7 0.426 75.0 19.1
    400 -16.7 -4.0 13.0 3.1 2196.6 1.967 1767.5 0.460 80.9 19.3
    425 -20.7 -4.7 14.8 3.3 2145.6 1.922 1686.4 0.494 87.0 19.5
    450 -25.3 -5.4 16.8 3.6 2095.3 1.877 1608.2 0.530 93.2 19.8
    475 -30.3 -6.1 18.9 3.8 2045.6 1.832 1532.8 0.566 99.6 20.0
    500 -35.8 -6.8 21.2 4.0 1996.7 1.788 1460.4 0.603 106.1 20.3
    525 -41.8 -7.6 23.6 4.3 1948.4 1.745 1390.6 0.641 112.8 20.5
    550 -48.5 -8.4 26.3 4.6 1900.9 1.703 1323.6 0.680 119.7 20.8
    575 -55.7 -9.3 29.0 4.8 1854.1 1.661 1259.3 0.720 126.7 21.0
    600 -63.6 -10.1 32.0 5.1 1808.1 1.620 1197.6 0.761 133.9 21.3

    26 Jun 2006 17:05:09, JBM [http://www.eskimo.com/~jbm]

    and here it is at the 50fps increase in MV from 3100fps to 3150fps with a .400 BC

    Trajectory Output
    Input Data
    Ballistic Coefficient: 0.400 G1 Bullet Weight: 165.00 gr
    Diameter: 0.308 in

    Muzzle Velocity: 3150.0 ft/s Chronograph Distance: 10.0 ft

    Sight Height: 1.75 in Sight Offset: 0.00 in
    Zero Height: 0.00 in Zero Offset: 0.00 in
    Azimuth: 0.00 MOA Elevation: 0.00 MOA
    LOS Angle: 0.0 deg Cant Angle: 0.0 deg

    Wind Speed: 10.0 mph Wind Angle: 90.0 deg
    Target Speed: 10.0 mph Target Angle: 90.0 deg

    Temperature: 59.0 ?F Pressure: 29.92 in Hg
    Relative Humidity: 0.0 % Altitude: 0 ft

    Vital Zone Radius: 5.0 in Std. Atmosphere at Altitude: No
    Corrected Pressure: Yes Target Relative Drops: Yes
    Zero at Max. Point Blank Range: No
    Calculated Parameters
    Elevation: 4.99 MOA Azimuth: 0.00 MOA

    Atmospheric Density: 0.07647 lbs/ft3 Speed of Sound: 1116.5 ft/s

    Maximum PBR: 373 yds Maximum PBR Zero: 318 yds
    Range at Max Height: 178 yds Energy at PBR: 1926.9 ftlbs

    Sectional Density: 0.248 lbs/in?

    Calculated Table
    Range Drop Drop Windage Windage Velocity Mach Energy Time Lead Lead
    (yds) (in) (moa) (in) (moa) (ft/s) (none) (ftlbs) (s) (in) (moa)
    100 1.6 1.6 0.7 0.7 2909.2 2.606 3100.3 0.099 17.4 16.6
    125 1.9 1.4 1.1 0.8 2849.1 2.552 2973.5 0.125 22.0 16.8
    150 1.8 1.2 1.6 1.0 2789.8 2.499 2851.0 0.152 26.7 17.0
    175 1.5 0.8 2.2 1.2 2731.3 2.446 2732.7 0.179 31.5 17.2
    200 0.9 0.4 2.9 1.4 2673.6 2.395 2618.4 0.207 36.4 17.4
    225 -0.0 -0.0 3.7 1.6 2616.6 2.344 2507.9 0.235 41.3 17.5
    250 -1.2 -0.5 4.7 1.8 2560.3 2.293 2401.3 0.264 46.4 17.7
    275 -2.8 -1.0 5.7 2.0 2504.8 2.243 2298.2 0.294 51.7 17.9
    300 -4.7 -1.5 6.8 2.2 2449.9 2.194 2198.6 0.324 57.0 18.1
    325 -7.0 -2.0 8.1 2.4 2395.7 2.146 2102.4 0.355 62.4 18.3
    350 -9.6 -2.6 9.5 2.6 2342.2 2.098 2009.5 0.386 68.0 18.6
    375 -12.6 -3.2 11.0 2.8 2289.3 2.051 1919.9 0.419 73.7 18.8
    400 -16.1 -3.8 12.7 3.0 2237.2 2.004 1833.3 0.452 79.5 19.0
    425 -20.0 -4.5 14.5 3.3 2185.6 1.958 1749.9 0.486 85.5 19.2
    450 -24.3 -5.2 16.4 3.5 2134.7 1.912 1669.3 0.521 91.6 19.4
    475 -29.2 -5.9 18.5 3.7 2084.5 1.867 1591.7 0.556 97.9 19.7
    500 -34.5 -6.6 20.7 4.0 2035.0 1.823 1517.0 0.593 104.3 19.9
    525 -40.3 -7.3 23.1 4.2 1986.2 1.779 1445.1 0.630 110.9 20.2
    550 -46.7 -8.1 25.6 4.5 1938.1 1.736 1376.0 0.668 117.6 20.4
    575 -53.7 -8.9 28.4 4.7 1890.8 1.694 1309.6 0.707 124.5 20.7
    600 -61.3 -9.8 31.2 5.0 1844.2 1.652 1245.8 0.747 131.5 20.9

    26 Jun 2006 17:06:40, JBM [http://www.eskimo.com/~jbm]
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  • gunnut505gunnut505 Member Posts: 10,290 ✭
    edited November -1
    EXACTLY what I was looking for; Muchisimas Gracias Senor!
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  • walliewallie Member Posts: 8,595 ✭✭✭
    edited November -1
    Your Welcome[:)]
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  • JustCJustC Member Posts: 16,056 ✭✭✭
    edited November -1
    Just a hint, as long as you are SURE of your chrony's avg velocity, you have EVERY variable covered other than BC. So when you shoot at each distance, you record your drops relative to what the original chart stated, and you adjust the BC in the table and re-run the calculation until the drops reflect the small differences between the original and your actual results. Once you hit on the right BC number, the chart will match your actual POI for a looooong way.[;)]
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