Is The Extra Millimeter Worth It

9x18 Makarov does 2d pi damage vs 2d-1 pi for .380 ACP.

As a practical matter, the differences in range don't come up.  Hardly anyone drops the points into Guns (Pistol) for it to show.

Recoil though, that will have an effect.

As calculated earlier, my Guns/TL8 (Pistol) skill is 15.

At 10 yards, we have a hapless NPC.

15 for skill
-4 for range

Not bothering to take time to aim.

11 or less to hit, just a bit better than a 50-50 (62.50%) shot for a single hit to the body.

Now recoil factors in.

To land the second round with Makarov I'd need to roll an 8 or less and for the third a 5 or less.  That's 25.92% and 4.62% respectively.

With .380 I need a 9 or less then a 7 or less.  37.50% and 16.20%.

So with .380 I'm 50% more likely to get a second hit and a bit more than three times as likely to land three.

Since the average skill roll with 3d6 is going to be a 10, I'm only going to hit with one round anyway on average.

2d pi gives a range of 2-12 points of damage, averaging to 7.
2d-1 pi gives a range of 1-11 points of damage, averaging to 6.

I used to know how to do the math to figure out the damage spread... alas.

Let's change the range to the traditional self-defense distance of 7 yards.  This changes the range penalty to -3 and our odds of hitting a bit from 11 to 12 for that first shot.  9x18 will need a 12, 9, and 6; .380 will need a 12, 10 and 8.

That means, on average, I will hit twice with the shorter round.

That also means that I would do 7 points with the Mak and 12 with the .380.