In a single turn, a 'Mech may punch with one or both arms. It can deliver a punch using its arm or fire the weapons on that arm, but it may not do both. Weapons mounted in the torso, legs or head may be fired in the same turn as a punch attack is made without affecting the punch.
All punch attacks must be made against targets in the attacking 'Mech’s forward or side firing arcs. If the target is in the right or left arc, only the right or left arm, respectively, may punch. A 'Mech cannot make a punch attack using a shoulder that suffered critical damage. Likewise, any arm actuator damage on the punching arm makes success more difficult and reduces the damage inflicted.
A punch attack has a Damage Value of 1 for every 10 tons (or fraction of 10 tons) that the attacker weighs. Reduce the damage by half for each upper or lower arm actuator damaged or not present, with these effects being cumulative. In other words, if both arm actuators are missing or damaged, reduce the attack damage to one-quarter of its original value (round fractions down, to a minimum of 1).
Determine damage location by rolling 1D6 and consulting the appropriate column of the 'Mech Punch Location Table based on whether the 'Mech is a biped or four-legged design.

Multiple Targets: A 'Mech can make two punches at two different targets and ignores the secondary target modifier.

Missing Actuators: A 'Mech does not need hands (or hand actuators) to punch. However, 'Mechs not equipped with a hand on the punching arm must add the +1 modifier as for a hand actuator critical hit. Likewise, 'Mechs that do not come equipped with a lower arm actuator on the punching arm must add a +2 modifier to the to-hit number (in place of the +1 modifier for punching without a hand actuator), and the punch inflicts only half the standard damage (round down).