Hello Jim,
here are some thoughts about OPFIRE which i collected from other players over the years:
Opp fire for nighttime- short
Recon unit-no fire in all categories. The unit does not want to fire at an enemy unit and be spotted.
AT gun-long range for soft and armor for 76mm, 85mm, and 88mm AT gun, no fire for infantry. Short to medium for 37-50mm AT guns. They have to be close to get any kind of hit on any armored vehicle after 1941. If the AT gun you are attacking is shooting you infantry, you know that you can make him take his shots are infantry instead of your armor. Infantry is much harder to kill with AT guns.
Infantry unit-long range for armor because long range is one hex with armor. Russian infantry perhaps short, because their fire is not all that effective. German infantry-med. Long range, or set according to how far one can see to shoot.
Armor Fire on Infantry- may be set to fire at infantry at short range only so as not to use opp fire needlessly , yet keep off the infantry. Russian infantry generally cannot harm a German tank. Vice versa is not true, esp. in 1944.
By Leto:
DO NOT USE OPFIRE!!
Why?
1) You do not have control over what you fire at (limited if you set range and target selection)
2) You never know if it will be triggered.
3) Opfire does not allow you to take advantage of retreats (AFV backsides) or disruptions.
4) Most often, you will be facing the enemy at his strength (such as 22 frontal armour defence on hetzers while they protect their vulnerable 3 strength backsides)
5) Smoke can always be used to soak up opfire with stronger units, and in many cases, extremely strong units can render a defense impotent (IE. King Tiger moves into hext with AT, Engineers and T-34's... Good chance not one of those is going to scratch the king of kitties)
When to use opfire:
1) When range is limited (infantry in a one LOS hex, such as behind a hill or in a town/city).
2) When covered arcs of LOS will not allow AFV's to be spun around by opportunistic opfire to be then shot in the bum.
3) When you have strong armour and much of it that covers all LOS points of enemy approach conjointly (this rarely happens)
4) When defending a hex that is out of LOS with 2-3 units so that other units that do not have opfire turned on will not be sighted and hex cannot be overrun.
5) When looking to ambush lorried (soft) units.
steffen