Are there separate body-part damage modifiers for Team Fortress 2?

I know headshots are a critical if you're a sniper, or if you're a spy using the Ambassador, because it's labeled in the weapon description. I can probably assume it is the same for any other weapon, but are there separate modifiers for the legs, arms, torso, and chest?

For example, when I am playing Heavy and get caught in a close range ambush with another Heavy, should I aim for their head, or does it really matter?

Solution 1:

There is no difference in damage from where you aim, with the exceptions of headshots for certain weapons.

Your example with the heavy, aiming for the head will not make a difference, what does make a difference in a lot of weapons' damage though is the distance of fire. The closer to are to the opponent the more damage you will do. Of course, this means they are closer and can do more damage to you as well, but this is why ambushing and surprise are always good ideas.

Solution 2:

Interestingly enough, this video does shed some light on some plausible body-part damage reduction:

Essentially, the jist of the video is that for some strange reason, the damage only hits up to 99 points of damage on the head for the grenade launcher, while bodyshotting yields more than 99 damage.