DomsPlaying
Member
press the left d-pad then hold RT and release when you have a good area to throw the grenade. If you hold the left d-pad, you can switch between grenades before using it.
I don't know about the pistol. It has infinite ammo, so it probably can only be used if you are using the shield perk (you can only use a pistol with the perk).
Oh crap thanks so much on the grenade tip! Gotta actually press Left on D-Pad not hold it. It was driving me crazy.
As for the pistol, I found if you go to inventory and re-equip it then you can use it but once you change it goes back to being not selectable. Pressing or holding Y (on Xbox) only changes between the two larger guns. Might be just for the skill or when you run out of primary ammo..