The View From North Central Idaho - One shot, one kill at 2100 meters

Monday, February 04, 2008

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Ry reports on a new Army sniping record from Afghanistan by a Arfcom member. Awesome!

If you are wondering at all the amazing sniping shots coming out of Afghanistan you aren't alone. I knew the high altitude would make a difference but I didn't know exactly how much until I ran some numbers through Modern Ballistics. Below you see the numbers for the .50 BMG shooting a high end bullet/cartridge with a gun zeroed at sea level for 1000 yards at a target at 2300 yards (2100 meters) away for various altitudes. Notice the difference in expected group size as the altitudes goes from 0 to 10000 feet. Notice the windage difference. All those things help but still, the shooter and spotter had to be top notch and have a little luck as well. Assuming a target of 18 inches wide and 24 inches tall the altitude difference changed the odds of a hit from about 10% to 20% (not shown).

Good job SnakeaterM24!

Modern Ballistics Data Created: 02/04/08 09:24:30

Firearm: Default
Cartridge: .50 BMG HMI with 750 gr. A-MAX
Conditions: Standard Conditions.
Range: 2300
Altitude (ft): 0 1000 2000 3000 4000 5000 6000 7000 8000 10000

Drop (inches)         2263   2193   2129   2070   2016   1966   1920   1877   1837 1765
Height (inches)      -1609 -1539 -1475 -1416  -1362 -1313  -1267 -1224 -1184 -1112
Height (moa)        -66.84 -63.93 -61.26 -58.82 -56.58 -54.52 -52.61 -50.83 -49.16 -46.17
Height (mils)       -19.44 -18.60 -17.82 -17.11 -16.46 -15.86 -15.30 -14.79 -14.30 -13.43
Windage (inches)    258.89 244.21 230.39 217.47 205.43 194.19 183.72 173.94 164.81 148.27
Windage (moa)        10.75 10.14   9.57   9.03   8.53   8.06   7.63   7.22   6.84   6.16
Windage (mils)        3.13   2.95   2.78   2.63   2.48   2.35   2.22   2.10   1.99   1.79
Mid rng Ht (in)       78.8   79.2   79.5   79.8   80.2   80.5   80.8   81.1   81.4   81.9
Midrange (yds)       532.1 535.4 538.6 541.8 544.9 547.9 550.8 553.7 556.4 561.8
Zero (yds)          1000.0 1008.1 1016.0 1023.6 1031.2 1038.7 1045.9 1053.0 1060.0 1073.4
Near zero (yds)        5.3    5.3    5.3    5.3    5.3    5.3    5.3    5.3    5.3    5.3
P.B. Size (in)      157.66 158.35 159.03 159.69 160.33 160.95 161.56 162.15 162.72 163.82
P.B. Range (yds)      1182   1192   1202   1212   1222   1231   1240   1249   1258   1275
Velocity (ft/S)       1118   1157   1200   1245   1290   1335   1380   1425   1469   1553
Energy (ft-lbs)       2082   2229   2397   2581   2772   2970   3173   3382   3593   4018
PF                     839    868    900    934    968   1002   1035   1069   1102   1165
Time (S)             3.941 3.857 3.779 3.705 3.637 3.573 3.514 3.458 3.406 3.312
Group (inches)       81.20 77.10 73.25 69.68 66.37 63.31 60.47 58.02 55.56 51.17
Group (moa)           3.37   3.20   3.04   2.89   2.76   2.63   2.51   2.41   2.31   2.12
Group (mils)          0.98   0.93   0.88   0.84   0.80   0.76   0.73   0.70   0.67   0.62
Groups <= desired    0.00% 0.00% 0.00% 0.00% 0.00% 0.20% 0.40% 0.60% 1.20% 1.20%
1 grp of <= desired    0.0    0.0    0.0    0.0    0.0 500.0 250.0 166.7   83.3   83.3
-----
Constants:
M.V. (ft/S)        2794   M.V. SDev (fps)    10.0   B.C.               1.050
Mass (grains)      750    Sight Ht (in)      1.50   Indicated SA (moa) 27.19
SA Offset (moa)    0.00   Incline (deg)      0      Wind (mph)         10
Wind error (mph)   2      Wind (deg.)        90     Temp (F)           59
Barometer          29.53 Gravity            32.17 Shots per group    5
Bullet acc. (moa) 0.50   Desired Grp (moa) 1.00   Group Simulations 500
----
Firearm name: Default
Firearm notes:
Cartridge name: .50 BMG HMI with 750 gr. A-MAX
Cartridge notes: BC is for Hornady A-Max. MV is for max load of H50BMG.
Conditions name: Standard Conditions.
Conditions notes:

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Joe Huffman Monday, February 04, 2008 9:44:42 AM (Pacific Standard Time, UTC-08:00)