Grenade Luncher ranges?

[weswood]

Going by the rules, an M203 (just for example) has a Range of 100 and an Indirect Fire Range of 400

The listed range of 100m is supposed to be short, medium would be 200m, long would be 400m, and extreme would be 800m, yet the IFR range is 400m. What I've read the max effective range is 400m, if I remember right.

I've never fired a grenade launcher. At what point does it go from direct fire to indirect fire?

I'm thinking anything under 100m would count as direct fire, from 100 to 400 m would be indirect.

Thanks