Yeah,ever take out a 20mm quad with a ATR? I got Matt Book's Like that once.
I believe you cannot do it with a normal ATR but only with a 20mm ATR.
"C13.24 vs PERSONNEL: An ATR can be used against Personnel targets with one FP as Small Arms Fire (no To Hit DR is necessary and therefore it may be used as part of a FG but it has no Long Range capability; i.e., it may not be fired beyond 12 hexes). An ATR leaves no Residual FP even if it attacks as part of a FG. Only 20L (i.e., 20mm) ATR may use the Infantry Target Type and AP HE equivalency."
To target the Gun, the normal ATR would need to use ITT, which is prohibited. With an ATR attacking as Small Arms, you would get a 1MC at best, which can't destroy the Gun.
With a 20mm ATR, you have a HE Equivalency of 2FP, with which you could score a Direct Hit. A DR of 2 would result in a K/1 which is enough for AP to destroy the Gun and its Crew as per C11.52.
"C11.52 AP: AP/APCR/APDS/ATR hits vs a Gun are resolved using the same mechanics as HE hits, but using HE Equivalency (8.31). The Gun and any manning Infantry are destroyed by a CH/any K/KIA result. A MG attacking alone, an ATR attacking as Small Arms, or an ATR/MG attacking as part of a FG, may cause Gun Destruction only as per A9.74."
So conceivably Matt's 20mm FlaK-Vierling should still be alive and kicking...
Edit:
Just noticing, that this is the SK-corner. What I said above is true for ASL. Dunno about SK.
von Marwitz