Dan,
There is a two step process here.
Step One
Determine if you hit. This is where the Defensive Modifier (DM) of your target (either infantry or vehicle or structure) is applied. If you are successful in the roll to hit then proceed to step two. If you are not successful (ie missed) then based on the type of ammo used (AP vs HE) determine the location where the round landed. If AP then skip this. If HE use the table 7.2 "Direct Fire Deviation" (p. 7.3) to figure where the HE (or HEAT) round landed.
Step Two
If successful, determine the "Hit" result. This is where you choose (based on ammo type used) the results of the hit. This is determined on the target.
- If the target is a vehicle then its Offensive value (OV) of the ammo vs the Defensive value (DV) the target. The net of OV - DV gives you the Kill table row.
- If the target is infantry (stand or weapons team) then it's Firepower value (FP) + or - FP modifiers straight to the Kill table row.
The Defensive modifier (DM) is always applied in determining the "To-Hit" step. Hope this helps
As for the "historical" account of a Boys ATR vs MG in North Africa. Here's my MP take on this.
Player one (w/ Boys ATR) has a target of player's MG. The Boys ATR does not have a HE or HEAT ammo choice only AP. The MG doesn't have an independent Defensive Value (DV) since it's integral with the infantry team crew. So player one doesn't have a OV vs DV option only the FP option. However, the Boys ATR doesn't have an FP value!! Oh the conundrum....... Rules to the rescue.
(There is a section in the rules that covers this!! <grin>) Using the rule Small Caliber from MCR p 8.1 it states:
Small Caliber – Any weapon up to 30mm in size and not listed on the Infantry Equipment Table is considered Small Caliber. To determine the base Fire Power, add +10 to the rounds AP Offensive Value (AP OV).
Hizzah!! Conundrum solved!!
Boy ATR is 14mm AP OV is 3. Per above rule add 10 and now the ATR has a FP value of 13. Work out FP attack against the MG team and press forward. History is proven once more.
Forgive the snark, I couldn't help myself.
Hope this helps.
Thanks