diff --git a/OpenRa.Game/Combat.cs b/OpenRa.Game/Combat.cs
index 9d42af2457..87e30467e2 100644
--- a/OpenRa.Game/Combat.cs
+++ b/OpenRa.Game/Combat.cs
@@ -39,7 +39,7 @@ namespace OpenRa.Game
 
 		static float GetMaximumSpread(WeaponInfo weapon, WarheadInfo warhead)
 		{
-			return (int)(warhead.Spread * Math.Log(weapon.Damage, 2));
+			return (int)(warhead.Spread * Math.Log(Math.Abs(weapon.Damage), 2));
 		}
 
 		static float GetDamageToInflict(Actor target, int2 loc, WeaponInfo weapon, WarheadInfo warhead)