I copied this from somewhere 13 years ago; the zeroing range is 25 meters. M193 ball will be back at 0 at @ 265 meters.
trajectory (in.) drop (inches) drift (inches)* From 20" M16A1 for M193, 20" M16A2 for M855 issue sight 2.5" above bore.
range M193 M855 M193 M855 M193 M855 M193 M855
(meters) MV MV TR TR Drop Drift 5MPH
0 3,200 3,100 -2.5 -2.5 0.0 0.0 0.0 0.0
100 2,774 2,751 +2.8 +4.4 -2.2 -2.3 1.3 1.1
200 2,374 2,420 +2.7 +5.8 -9.9 -10.2 5.8 4.9
300 2,012 2,115 -4.9 0.0 -25.1 -25.3 14.2 11.8
400 1,680 1,833 -23.0 -15.0 -50.8 -49.5 27.6 22.4
500 1,373 1,569 -56.2 -42.9 -91.6 -86.7 47.5 38.0
600 1,106 1,323 -113.1 -88.2 -156.1 -141.3 76.4 59.5
700 995 1,106 -206.8 -156.1 -257.3 -220.9 113.5 88.4
800 927 1,010 -339.9 -267.7 -398.0 -339.2 156.1 124.9