ballistic data for 9mm through 10.5" AR
- Thread starter FPembleton
- Start date
14.5" should be similar:
http://www.thehighroad.org/archive/index.php/t-65252.html
http://www.thehighroad.org/archive/index.php/t-65252.html
Borrowed from the maryland shooters site
Zeroing a 9mm AR Carbine
by LTC Chuck Santose
I made the assumption you're shooting 115gr 9mm Parabellum, not 124gr 9mm NATO for this one.
Recommend you zero at 25 yards. With this zero the bullet is no more than an inch from line of sight (the dot or your iron sights) from about 15 yards to 100 yards. That is the bullet is under [inside, not lower] the dot at all times. You only need to hold "up a dot" at 125 yards and up 2 at 150. Comparison of 25 yard and 50 yard BSZs are below:
Range 25 50 75 100 125 150 175 Yards
25 Yard Zero Path (LOS) 0.0 1.2 0.9 -1.1 -5.1 -11.1 -19.3 inches
MOA Adjust 0.0 D2.4 U1.2 U1.1 U3.9 U7.1 U10.5 moa
50 Yard Zero Path (LOS) -0.6 0.0 -0.9 -3.6 -8.2 -14.8 -23.6 inches
MOA Adjust U2.4 0.0 U3.4 U3.4 U6.2 U9.4 U12.9 moa
D= Down, U=Up
With a 25 yard zero your bullet peaks at 60 yards and is less than 1-1/2 inch above line of sight. Any target closer than 100 yards the bullet will strike somewhere within the 3.5 or 4MOA dot if you do your part.
I don't like the 50 yard zero because the bullet is always low and is dropping like a stone past 75 yards. You'll have to hold up a dot at 100 yards and don't have any midrange advantage.
Zeroing at 100 yards the bullet peaks at 2" above line of sight and is otherwise close to the 25 yard zero -- but a hassle to keep walking down range to compute the group size.
Try zeroing the iron sights, then the CCO (M68/Aimpoint) at 25 yards. It's critical to zero with both eyes open with the CCO as that's how you'll shoot it in the field. Note it's important to really measure group centers because the difference at between zeros isn't much at 25 yards.
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Editor's Note: After Chuck did the workup on 115gr 9mm I though we should also do one on the 147gr (sub-sonic) JHP round (BC of .164). As that is more likely to be used by supressed 9mm AR sub-guns. Rex was kind enough to provide muzzle velocity information.
Range 25 50 75 100 125 150 175 Yards
25 Yard Zero Path (LOS) 0.0 0.204 -2.1 -7.1 -14.8 -25.4 -39.1 inches
MOA Adjust 0.0 D0.39 U2.6 U6.8 U11.3 U16.2 U21.3 moa
50 Yard Zero Path (LOS) -0.1 0.0 -2.4 -7.4 -15.3 -26.1 -39.9 inches
MOA Adjust U0.4 0.0 U3.1 U7.2 U11.7 U16.6 U21.7 moa
D= Down, U=Up
Recomendation is to keep the 25 yard zero. To tell the truth there isn't that much difference between the two zeros. But I'd have to go with the 25 yard zero as being the better of the two. The 25 yard can be done on most inside ranges and is a bit flatter (though not by much). Looks like the use of 147gr 9mm is pretty much limited to 75 yards for precision shooting - no more than 100 yards for COM.
Zeroing a 9mm AR Carbine
by LTC Chuck Santose
I made the assumption you're shooting 115gr 9mm Parabellum, not 124gr 9mm NATO for this one.
Recommend you zero at 25 yards. With this zero the bullet is no more than an inch from line of sight (the dot or your iron sights) from about 15 yards to 100 yards. That is the bullet is under [inside, not lower] the dot at all times. You only need to hold "up a dot" at 125 yards and up 2 at 150. Comparison of 25 yard and 50 yard BSZs are below:
Range 25 50 75 100 125 150 175 Yards
25 Yard Zero Path (LOS) 0.0 1.2 0.9 -1.1 -5.1 -11.1 -19.3 inches
MOA Adjust 0.0 D2.4 U1.2 U1.1 U3.9 U7.1 U10.5 moa
50 Yard Zero Path (LOS) -0.6 0.0 -0.9 -3.6 -8.2 -14.8 -23.6 inches
MOA Adjust U2.4 0.0 U3.4 U3.4 U6.2 U9.4 U12.9 moa
D= Down, U=Up
With a 25 yard zero your bullet peaks at 60 yards and is less than 1-1/2 inch above line of sight. Any target closer than 100 yards the bullet will strike somewhere within the 3.5 or 4MOA dot if you do your part.
I don't like the 50 yard zero because the bullet is always low and is dropping like a stone past 75 yards. You'll have to hold up a dot at 100 yards and don't have any midrange advantage.
Zeroing at 100 yards the bullet peaks at 2" above line of sight and is otherwise close to the 25 yard zero -- but a hassle to keep walking down range to compute the group size.
Try zeroing the iron sights, then the CCO (M68/Aimpoint) at 25 yards. It's critical to zero with both eyes open with the CCO as that's how you'll shoot it in the field. Note it's important to really measure group centers because the difference at between zeros isn't much at 25 yards.
--------------------------------------------------------------------------------
Editor's Note: After Chuck did the workup on 115gr 9mm I though we should also do one on the 147gr (sub-sonic) JHP round (BC of .164). As that is more likely to be used by supressed 9mm AR sub-guns. Rex was kind enough to provide muzzle velocity information.
Range 25 50 75 100 125 150 175 Yards
25 Yard Zero Path (LOS) 0.0 0.204 -2.1 -7.1 -14.8 -25.4 -39.1 inches
MOA Adjust 0.0 D0.39 U2.6 U6.8 U11.3 U16.2 U21.3 moa
50 Yard Zero Path (LOS) -0.1 0.0 -2.4 -7.4 -15.3 -26.1 -39.9 inches
MOA Adjust U0.4 0.0 U3.1 U7.2 U11.7 U16.6 U21.7 moa
D= Down, U=Up
Recomendation is to keep the 25 yard zero. To tell the truth there isn't that much difference between the two zeros. But I'd have to go with the 25 yard zero as being the better of the two. The 25 yard can be done on most inside ranges and is a bit flatter (though not by much). Looks like the use of 147gr 9mm is pretty much limited to 75 yards for precision shooting - no more than 100 yards for COM.
