[Hobbes]

Simple action to "Ready" a weapon.  Gear access lowers this to Free.

Simple action to change the grenade from one setting to another.  Set different Grenades to different settings so the kind you need is typically ready to go.  For someone with a lot of dice in throwing you can likely set most of them to motion sensor and let them explode on impact.  'cause you'll hit your target 90% or more of the time.

Simple action to throw.

Properly set up, Free action ready the grenade (Tomahawk, whatever) you've got pre-set to what you need, Simple Action Aim, Simple Action Throw. 

[antaskidayo]

I think grenades are different from shurikens and knives that you can ready X grenades = Agility/2. 1 Combat Turn is 3 seconds, I think it will eat more time to enter how much delay the timer will be. So 1 simple action will ready 1 grenade, so a bola with 2-3 grenades will take 2-3 simple actions to set the timer before throwing - I think this is fair.

-I dont think motion sensors will be effective as there is the Right Back At Ya! interrupt action and the enemy caster can put a wall and intercept it mid-flight. 

[Jack_Spade]

If you link the grenades you only have to activate one - the other will go up out of sympathy 

[antaskidayo]

If you link the grenades you only have to activate one - the other will go up out of sympathy 

where can I find that mechanic?

[Jack_Spade]

You mean where can I find the rules that explosives will explode when they are in close proximity to other exploding explosives?
Right next to the rules that your character needs to breath to stay alive.

[antaskidayo]

Hmmm, yeah fair enough, if they are tied together on a bola the pressure wont push them away - but that makes it too OP if the thrower could throw like 3 boom bolas then that would be 6-9 grenades. The only chance would be to quickly find the grenade with the activated timer and do something about it, A caster putting up a wall to block the grenades in mid flight or have movement to quickly get out of range. 

[Darzil]

Bear in mind that bolas (including boom bolas) are an exotic weapon, so don't use thrown, and I personally wouldn't allow them to be used with multiple attacks, as they are neither melee weapon nor firearms (I would allow it for knives and shuriken, but can't see the rules that do).

They are also thrown at a target, not as grenades at a location (the cinematic spin round and round target then when they stop, go boom), it is only on misses that you worry about scatter.

[antaskidayo]

Bear in mind that bolas (including boom bolas) are an exotic weapon, so don't use thrown, and I personally wouldn't allow them to be used with multiple attacks, as they are neither melee weapon nor firearms (I would allow it for knives and shuriken, but can't see the rules that do).

they are still thrown weapons even if they use the exotic weapon skill.

They are also thrown at a target, not as grenades at a location (the cinematic spin round and round target then when they stop, go boom), it is only on misses that you worry about scatter.

Bolas can do one of two types of damage based on their use.
When thrown to hit a target, make an Exotic Ranged Weapon
(Bolas) Attack Test (use the DV and AP stats on the left side of
the slash for monofilament bolas).

When thrown with the intent of wrapping around a
specific location on an opponent use the appropriate Called
Shot Location modifier to determine success. A standard bola
requires the target to make an immediate Agility + Gymnastics
[Physical] Test with a threshold of the attacker’s net hits; if they
fail, they fall prone.

they can be used in 2 ways - thrown at a target normally, and the other one that entangles the target

[Darzil]

Yes, but not thrown as grenades,