[Legbreaker]

An M203 using the stock standard HEDP round has a Pen (Penetration) of 4C.
2D6 are rolled (in almost all cases for heavy weapons) and added to the Pen. In this example, lets say we roll a 7 for a total Pen result of 11.

Now lets say the target is a lightly armoured vehicle, lets call it a BTR-80, and assume the shot hit. We then roll on the hit location table (page 217) using 1D6 and looking at the vehicle column. If the attack was from the side, we'd add 1 to the roll.

In this case, lets say the roll was 3, which means a hit on the hull, and the shot was from the front, so the AV will be 3 (BTR-80 page 75, HF3). We then take the 3 points of armour from the penetration result of 11 for a final penetration of just 8.

We can then look at the table on either page 260 or 218 and see a final Pen of 8 will give 1 minor damage. We then roll 1D6 on the minor hull damage section of the vehicle damage table which has possible damage results of 1 crewmember, Loader, 2 Passengers, Radio, or Major hull. Lets say we roll a 4 and therefore the result is passengers. Being an APC, if there are passengers aboard, two of them are subjected to 1D6 number of hits, each doing 1D6 points of damage to random locations. If the passengers have dismounted, the GM has the option of the attack doing either no damage at all, or destroying cargo.

Therefore, as we can see from the above example, a 40mm HEDP isn't going to destroy even a lightly armoured vehicle very often, although there is always a chance (could roll a major result), but it will still penetrate, and will give the occupants a bad hair day.

Also, ANY penetrating shot will require the crew and any passengers to roll for panic and possibly jump out of the vehicle (Bail out, page 197).