[Lucean]

Is there someone who can tell me how the rules for the grenade launcher of the Ares Alpha worked in SR3?
I already know that you used the skill of the main weapon, but was it unmodified? Could you apply the specialisation or did you base it on the (reduced) weapon skill?

[T2-Keks]

To use grenade launchers of any kind you had to use the skill "launch weapons", which included guided- and unguided missiles, grenade launchers and spotter (to help guide missiles). It is linked to the intelligence attribute and the gunnery skill.

So basically no way to use the grenade launcher with the assault rifle skill.

[Shaidar]

Launch Weapons (Intelligence)
This skill covers the use and targeting of any device that fires a missile, rocket, or other explosive projectile (such as grenades), including mortars (but not in or on vehicles). This skill covers manual and sensor-enhanced fire, and also governs the use of both specific grenade-launching weapons and underbarrel grenade-launching mounts. The Spotter Specialization can be used for any targeting tests. (B/R)
Default: Gunnery. Note that if a character has a weapon with an underbarrel grenade launcher, the player can default to that weapon’s skill as if defaulting to a base skill within the same grouping (+2 modifier to the target number, 1/2 Combat Pool).
Specializations: By specific missile or rocket type, Grenade Launchers, Spotter

Underbarrel launchers have an exception however.

[T2-Keks]

Lol, i never noticed that

[Tarislar]

Ditto,  I'm going to have to pull out the old SR3 book & reread that.