QUOTE (Epicedion @ Oct 18 2013, 11:50 PM)

Back to this:
An HE (14P -2AP) grenade at ground zero against an average mook (Body 3) with an armor vest (Armor 9) will do about 11P, incapacitating him but not killing him. Every meter reduces this by 2P until the damage is below the modified 7 armor and it becomes Stun. The track looks like this (1m steps): 11P, 9P, 7P, 5P, 3S, 1S, 0.
A fragmentation (16P +5AP) against the same target will do about 11P, same result. Every meter reduces this by 1P until the damage is below the modified 14 armor and it becomes Stun. The track looks like this (1m steps): 11P, 10P, 9P, 8S, 7S, 6S, 5S, 4S, 3S, 2S, 1S, 0.
One problem, Grenades do full 2 more damage than that (still ignoring chunky salsa!). My physical book says 18P for frag and 16P for HE. This might not seem much but it is a world of difference between getting 9 boxes and still live/be awake and 11 boxes and getting knocked out.
QUOTE (Epicedion @ Oct 18 2013, 11:50 PM)

This shows that an HE grenade against a common target has an effective serious injury radius of 3m, and an expected damage radius of 5m.
The frag grenade against a common target has an effective serious injury radius of 2m, and an expected damage radius of 10m.
Conclusions and Observations:
1) Anyone prepared for combat (that is, wearing at least an armored vest) is likely to survive a point-blank grenade blast, assuming no other injuries. Security armor almost guarantees that the damage will be Stun.
2) Frag grenades are very dangerous to consider using indoors, since the blast radius is so high -- you have to throw at least 10m to keep out of the actual damage radius, which probably means at least long range (-3 dice pool), and which probably isn't happening indoors unless you're in a warehouse.
3) HE grenades are probably going to be thrown at least medium range (-1 dice pool).
4) Throwing to the other side of cover either means a Blind Fire penalty (-6 dice pool) since you can't actually see the target location, or throwing to a location you can see farther back. Combined with the above two points, this means that throwing a grenade at the feet of some guys in cover is going to be between a -6 and -9 dice pool penalty. Assuming you're an all-star quarterback with 15 dice, you'll still be crossing your fingers hoping for those 3 successes.
5) Grenades are a great way to injure a tight cluster of guys -- a group of guards in a small room, for example -- but they're expensive and can be tricky to use. When it comes down to dropping a single target, a 24 nuyen assault rifle burst of explosive rounds at 12P -3AP (-2 to defense) with 12 dice behind it will probably do more damage (12 dice vs 4, so 15P -3AP, so 12P) to the target, which is far more cost (24 nuyen vs 100) and action (simple vs simple+simple) efficient.
I don't need to care any about the aoe effect, that is just bonus. A underbarrel grenade launcher will hit your intended target with no penalties. Getting more than 3 hits has no effect whatsoever so any accuracy of 4+ is wasted since targets get no roll to defend.
AS a bonus, a frag grenade causes boxes of damage several meters from the impact, a HE grenade has much smaller effective zone but tends to be physical more (and sometimes a smaller effective area is desireable).
You need 30 damage resist dice to make a HE/Frag grenade to a mere "serious" injury instead of "Deadly" (SR3 terms but a good measure stick, 1 box is light, 3 is moderate, 5-6 is serious and 10 boxes is deadly, grenades are almost always deadly, but big orcs can reduce it to serious, sometimes even moderate but that is rare).
The problem isn't really that they work, the problem is that you have 18P ignoring all defences compared to 11P vs full defence dice pools with a regular gun (auto fire reduces defences but at a cost). Characters are presented a world of guns that targets a defence roll and a world of grenades that are pure "pve", rolls 3 hits and win.
More damage, easier to hit, bonus aoe effects, far less recoil, ...... any high threat fights will be with grenades only since they are far far far far superior, making guns/melee/spellcasting a small niche (using silencers ofc). It is a problem to ignore defence mechanics alltogether. Just like Direct combat spells were a serious issue in SR4 targeting a weak stat and ignoring all other defences.
I rather not let that happen since that kind of meta-play can destroy so many character concepts and washes out combat when it becomes apparent for everyone that it is really just about one trick.