Recently purchased a Colt M4, LE6920, and am going to the range this Friday night to zero it in. When I was in the army, we zeroed @ 25 Meter targets, which coincides with a 300 meter target as well, but the range I'm going to only has 100 yard areas, so I'm not quite sure how I'm going to effectively BSZ (Battle Sight Zero) at that distance.
I've got a target, but what should the rear elevation be set to? 6/3 -3 (or 6 if double clicks)? It's been a few years, but if I recall correctly the 6/3 is for 300-600 meters, so -3 should be 100M/Yards, correct? I've found an improved method, but this deals with tweaking the rear sight post and I'd rather not jack up the weapon if possible.