Just to verify/summarize:
The applied ammo effect damage for 'nades actually stuck to an enemy is determined by weapon base damage and any hip-fire penalties.
A charged whale gun or Arc won't change this damage amount? Or is that 100% wrong?
Thanks...
AFAIK the applied ammo damage will be the same as that of a single non-charged shot from any charged weapon, i.e. charging the weapon before the grenade impacts makes no difference either way. I'm reluctant to state this as fact because I've never thoroughly tested it, but it would be easy to do with a weapon like the Arc Pistol which has vastly different damage between charged and non-charged modes. Kalence seems to think that the Kishock does the same ammo damage either way, but the Arc's changes....interesting. Either way I don't think it applies to stickies.
Anyway, in the kishock's case it is comparatively among the best weapons in this regard because it does huge damage per shot and furthermore is unaffected by hipfire penalties. For the arc pistol it isn't much, though it is important to note that even the by far best weapon in terms of applying single projectile ammo damage (scoped Javelin) will only do like 900 something per grenade with incendiary IV, which isn't even enough to get a gold Cannibal down to half health, let alone make a dent in something like an Atlas' 25000+ Armor points in terms of TTK.
I generally don't bother with worrying about applied ammo damage when choosing a weapon because it is pretty insignificant, especially considering that it only applies to the single target which is stuck. Snipers are the best weapons if you really are concerned with that though, as even with hipfire penalties applied the higher damage per shot ones will still do more ammo damage than any other weapon (due to shotguns applying only a single pellet), nevermind that avoiding the penalty is easy if you are using the grenades to reload hide (or using a multishot sniper where you will probably be in scope for a while after throwing them anyway).