We're just going to do a single shot here, though rate of fire is also modeled, as is turret speed. We'll just assume they're both facing each other head on. We will also assume they have sighted each other, which is not a given as there can be vast differences in your sighting range and effectiveness based on what your tank is doing and what the other tank is doing. For example, a PzKfwIVF2 rushing forward would almost certainly be shot at by that T-70 before it realized the T-70 was there.
Ok, now let's say the PzKfw IVF2 shoots its first shot at the T-70. First, the 75mm/L43 has a To Hit number of 5 at 500 meters. It's almost a sure hit inside of about 425 meters, but the difficulty starts to climb after that. So the base roll to hit is a 5 or more on a d10.
Since this is the first shot at a target over 300m away, that's modified up to a 6. The T-70 also has a size modifier of 1 (it's a small tank) which makes this a 7. There are no modifiers for previous shooting, for either tank moving or for shell type (HEAT and HE are less accurate), nor are there modifiers for cover in this case. We'll say the Panzer already turned its turret the previous phase, so no penalty for that either. So, basically, we have to roll a 7 or more on a d10 to hit with our first shot, which gives us a 40% chance. After the first shot, this goes up to a 50% chance. Once we actually score a hit (any hit) on the target, this goes up by another 10% to 60% as it's considered to be an "acquired target". If we were shooting at the side rather than the front there would also be a bonus. Note that the "to hit" roll is open-ended, so a result of 10 has a 50% chance to end up being a 11-15, which allows "lucky shots" to happen (i.e. driving forward, turret turning, snap shot at 500m, ping! - highly unlikely, but possible
. Anyway, let's say we hit. To summarize: the initial shot gets a 40% chance at 500m, the second shot is 50%, the third shot (if a hit is obtained) is 60%. Otherwise , its stuck at 50%.
Its my opinion that this is woefully undermodelled. Its also such an important part of the game that I HOPE the designers reconsider this modelling.
Matrix has stated that the game can be modded as far as these hit numbers, but I do not think that the released game should be as far off as I consider this to be. In other words, we can use 'Rexfords-Hit-Mod-Pack' or something like that.
For a weapon like the German 75mmL43, hittinmg a target at 500m is no great feat. in fact, the Germans preferred shooting it out at much longer ranges. At this time in WWII, the StuGIII with the 75mmL43 and the PanzerIV with the same gun were probably the best AT systems around.
The elements of gun accuracy can be broken down into:
1. Estimating the distance
2. Estimating the speed (stationary in the above example)
3. Laying the weapon (adjusting sights)
4. Firing and observing the shot
5. Corrections based on 4
At 500m, even a 20% error in distance estimation will only put you off +/-100m. The gun systems dispersion will then be the major factor in realizing a hit or a miss.
There are many other factors but these are the major ones. Since these are Vets in this game, I would not appreciably factor in 'human-factors' that much.
My general impression is that the modeling is off by at least a factor of 2. that is, what they are modeling at 500m might actually take place at 1000m. The followup shots are way off, especially if a BOT (burst on Target) is obtained.
