High Explosive grenades do 16P -2AP damage and Frag grenades do 18P +5 AP. To put that in perspective, an Ares Predator V does 8P -1AP, Ares Alpha 11P -2, an Ares Desert Strike does 13P -4AP, and a Panther XXL does 17P -6AP. High Explosive Rockets/Missiles do 21P -2AP. Worn armor is uncapped (though you can only get the benefits of 1) and only +armor items has an encumbrance cap. Therefore it might be reasonable for most people to have 15 armor (12 Armor Jacket + 3 Helmet).
When you attack there's three detonation nodes (SR5O* 181-183). There's a bit of difference between thrown and launched grenades/missiles, but they are minor like scatter and minimum distance. The first is built in timer. To do this, you take a simple action and make a Skill + Agility [Physical] threshold 3 test. If you make the test, you land the grenade where you want. If you fail, it scatters in a manner similar to SR4 expect it's a 2d6 roll for direction. Once it lands, it explodes next combat turn at your Initiative Score -10.
Motion sensor means you set the grenades to explode on impact. This uses the standard attack rules. The target suffers a -2 Targeted by an Area-Affect Attack penalty to his defense test. If you succeed, you hit dead on. I don't know if net hits add to damage in this case. If you fail, you roll scatter as if you had 0 hits. Either way, it explodes instantly. The big question is what happens if you don't shoot a person directly, but the ground, a chair, or whatever. Even if you have to shoot 1m to the left of the "real" target, that's only -1DV damage. There's also no innate "dive for cover" rules against Area Effect attacks in SR5O where you can try to get further away.
The last is wireless link. This works like built-in timer grenades but instead you can explode them with a Change Wireless Device Mode action. If you have DNI to the grenades, this is a free action. If you don't have DNI to the grenades you need a wireless connection, it's a simple action and scatter isn't reduced by hits if you miss. I will admit I don't know if this is reasonable thing to do or a suicide plan since I'm still digesting the Matrix chapter.
Do note, that the grenade/explosive stacking rules from War! are Core now. This does mean you can use a SA grenade launcher (like the MGL-12) to fire a Semi-Auto Burst as a complex action which fires 3 grenades and gives the defender a -2 penalty to Defense. Technically this only works with motion sensor grenades since attacking with the others is a simple action.
*-Shadowrun 5th Edition Origins Edition