Hit Locations and Called Shots in OSR Games

I like OSR games to have a little bit of tactical depth, so for my game I'll be allowing called shots- i.e. people to specify that they want to hit someone in the hand, eye, etc.

I'll also be using a random hit location system, though not on most attacks– only when someone takes a wound or I otherwise need to specify where they got hit.  Since Esoteric Enterprises has a built-in wound system that already covers this, it might not see much use until my next campaign, but I came up with an idea for a hit location system, so here it is.

I've seen a few hit location charts, but most are more complicated than I'd like.  For my home game I want a hit location system that's quick, simple, and so easy to remember that I'll never have to refer back to the rules.

My solution: the clock face system.  

Imagine a person posed spread-eagled, with a clock over their body with its middle in the person's midsection.  Actually don't imagine it, just take a look at Ryu in the Vitruvian Man pose here:

That's easy to remember because you just need to think about a clock face, and a person roughly in that sort of pose.

These numbers are broad enough that each one covers a few locations.  Like 5 and 7 are the whole leg, 1 and 11 are both the neck and shoulder and maybe the upper arm and corner of the chest and back, 4 and 8 are both abdomen and hip, etc.

What if you want something more specific, like you want to know where on the head someone got hit?  Then it gets way more complicated, because you have to..actually just roll another d12 and interpret it the same way.

Even then, a little bit of human judgement is needed, but that would mainly be based on whether the attack is coming straight in like a spear, or swinging around like a warhammer.  Like for a head hit, a 12 could be either on the dome or the nose, a 6 could be either the chin or the mouth, etc.  But this system gets you 80% of the way there, and you'll never need to refer back to a chart in the middle of a battle.

If someone is behind cover and you roll a body part that's covered, just go with the exposed body part whose number is closest to what you rolled.

Okay, so called shots.  What I do here is just use the Pathfinder size chart, because it's sensible and unlike the 5E chart or anything else I could find, it goes down to finger-sized objects.  Here's an abridged version I typed up:

So if you want to tear open someone's backpack or sunder their halberd, that's a +1 to the DC.  Disarming someone of a longsword would be +2.  Disarming someone of a dagger would be +4 (I'd combine the size of the dagger and the hand since really you could attack either).  Cutting off the finger with the magic ring, or breaking the lich-king's magic pendant, that's a +8.

If the enemy is bigger than a human, just work backwards from whatever size they're at.  So disarming an orge (large) of a dagger (+2 since it's one size category bigger) would be +3 to the DC– +2 for a tiny target, but also subtract back out the -1 you presumably got for the ogre's size to begin with.

Note that the Pathfinder size chart goes two levels higher than that.  However, I think monsters bigger than Huge, and sometimes maybe Huge monsters as well, are better handled as inverse swarms.

Since there's a chance you miss your called shot but hit the target anyway, I'd say if the DC mod is +2 or greater and you miss by half or less of the mod, you score a normal hit.  So if you take a +8 to try and hit the lich-king's magic pendant and fall 3 short of the modified DC, you just hit him in the chest and score a normal hit.