Heavy Weapons

The following conversion of Heavy Weapons are meant to function hand in hand with the rules for Armor Conversion and Barrier Defense and make little sense otherwise.

The HW Damage Conversion table is at its heart an expansion of the firearm conversions however the size of these weapons bring a certain factor into sharp focus. While there are differences between weapons even of the same size in real life, the exponential nature of HERO causes them to disappear for the simple reason that the system isn't finely enough grained to make anything but heavy variation visible.

Thus the following assumes best performance in class as its baseline and values like Stun Modifier and Piercing are fixed for each group of weapons instead of a conversion formula being presented. Conversions of weapons known to under perform can be handled by applying a negative modifier to one or more elements of the final result. As normal the values are for solid shot projectile although that type of ammunition is basically never fire from today's heavy weapons.

HW Damage Conversion
Caliber (inch)	Metric (mm)	Damage	Penetration	Stun	Piercing
0.50	12.7	3d6K	9	+4	3
0.71	18	3d6+1K	10	+4	4
0.98	25	3 1/2d6	11	+4	5
1.38	35	4d6-1	11.5	+4	5
1.77	45	4d6	12	+4	6
2.17	55	4d6+1	13	+4	6
2.76	70	4 1/2d6	14	+4	7
3.11	79	5d5-1	14.5	+4	7
3.46	88	5d6	15	+4	7
3.94	100	5d6+1	16	+4	8
4.72	120	5 1/2d6	17	+4	8
5.00	127	6d6-1	17.5	+4	8
5.98	152	6d6	18	+4	8
8.00	203	6d6+1	19	+4	9
12.00	305	6 1/2d6	20	+4	10
14.00	356	7d6-1	20.5	+4	10
15.00	381	7d6	21	+4	10
16.00	406	7d6+1	22	+4	11
18.00	457	7 1/2d6	23	+4	11

Penetration is the base DC value of the weapon and is used as per the rules for Barrier Defense. Stun is the Stun modifier applied if the weapon happens to hit a target that takes stun damage while Piercing represents the base points of Piercing added to the weapon. These points of Piercing do not have any levels of the Armor Piercing advantage applied to them.

After determining the base damage characteristics of the weapon, the final weapon performance is modified as per the following chart mostly due to the type of ammunition fired.

Heavy Weapon Modifiers
Type	Penetration Modifier	Damage Modifier	Piercing Modifier	Stun Modifier
AP	1	0	+4	0
APDS	2	-3	+6	0
APFSDS	3	-3	+9	0
APFSDS-DU	4	-3	+12	0
HE	-3	-6	-4	0
HEAT	3	0	+9	0
Semi-AP	0	0	0	0

Poor Ammo Quality	-1	0	-3	0
Short Barrel	-1	0	0	0

Positive Penetration Modifier refers to points of Resistant Piercing bought with one level of the Armor Piercing advantage allowing it to affect Barrier Defenses that typically buy one level of Hardened Defenses.

Poor Ammo Quality refers to those weapons that have known problems in ammunition production such as Iraq's APFSDS in the two Gulf Wars.

The Short Barrel modifier is for a number of mostly WWII weapons that used a shorter than normal gun. Examples include the 75mm on early versions of the M4 Sherman or the 50mm used on early versions of the Panzer III.

Actual conversion of weapons must keep in mind that certain weapons either cannot or will not use specific ammo types. Howitzers for example are unable to use any of the AP ammunition types and are almost never seen with HEAT rounds.

Example Heavy Weapons Damage
Weapon		Damage	Penetration	Piercing	Stun
US 25mm M242 Bushmaster
	HE	1 1/2d6K Ex	8	1	+4
	AP	3 1/2d6	12	9	+4

M72 LAW 66mm	HEAT	4d6+1	16	15	+4

US 105mm M68A1
	HE	3d6+1K Ex	13	4	+4
	APDS	4d6+1	18	14	+4
	HEAT	5d6+1	19	20	+4
	APFSDS	4d6+1	19	17	+4
	APFSDS-DU	4d6+1	20	20	+4

US 120mm M256
	HE	3 1/2d6 Ex	14	4	+4
	HEAT	5 1/2d6	20	20	+4
	APFSDS-DU	4 1/2d6	21	20	+4

Iraq 125mm 2A46M/ D-81TM
	HE	3 1/2d6 Ex	14	4	+4
	HEAT	5 1/2d6	20	17	+4
	APFSDS	4 1/2d6	19	14	+4