I did a quick check in SBP, and took some screenies.
"In excess of 1 mile". For the sake of simplicity, assume it means one and a quarter mile, that would be 1600 + 400 = 2000 meters.
Also assume, the enemy was hidding in a village, there was cover, he tried to hide and run around and after realising he was under attack he certainly did not just stand still in the open.
Below you see a couple of screenshots on a flat and featureless terrain. The tank is a M1A1(HA). Mind you, the sim is said to give quite accurate physics and visual dimensions of its sights, because real men use it for demonstration and training for the real hardware.
The setting is as such: I have set up BMP-2 (flank shown) at precise range of 1000m, 1500m, and 2010m (cannot help the 10 meters
) Attached to each BMP, in line formation, is infantry laying flat on the ground, facing the Abrams. They were placed exactly at these ranges , and in a was so that all three groups can be seen simultaneously in the sights.
The original pics are jpgs at 1680er resolution. I use imageshack to reduce them to 1280.
General overview:
Gunner'S primary sight, thermal, unzoomed (x4):
Gunner's primary sight, thermal, zoomed (x10)
Gunner's primary sight, optical, x10
Gunner's auxiliary sights
Commander's turret vision block
And Tatarataaaa: commander's cal.50 sight:
Mind you: we are talking about 1 1/4 mile. That means 2000m - the most distanced row of targets. One mile distance would be slightly behind the medium row of targets.
The gunner should have no problem to lay his crosshairs ointo a target the size of a man at ranges 1000, 1500 and 2000 meters. With the auxiliars sights it is more difficult, but still possible. The commander's cal.50 sights certainly enable him to target vehicles and hit them with a salvo, but you already expect some missing rounds here. Hitting a single man with only one round and the first shot witb these sights, repeatdly, and dispersion not messing up the ballistics at all, I assume to be almost impossible. You have dispersion even when firing rounds from a 25, 30 or 40 mm autocannon. The gunner can use the coax and lay sights on a man at 2000 m, still, even at below 1000m you would have a dispersion that make it extremely likely that you will need several salvos or one long one.
Note that the sights of the commander end line markings at the range of 1600 meters! There is no marking included for the 2000 m range.
The TC can rain fire on a group of people at that target, and with a long salvo he will hit many of them. But one shot per target only? No.
(BMP-2 is 2.45 m in height. So three quarters of its height, and you have a man 1.80 meters tall - that gives an idea of how high a standing man would appear in those pics.)