In an online Pathfinder game, I'm playing a crossbow sniper who uses the Reduce Person spell to help him be sneaky. That led me to look at the rules for using projectile weapons reduced and enlarged. And I found an inconsistency in Pathfinder that troubles me.
Under 3.5 D&D, the rules were clear. The D&D 3.5 Enlarge Person and D&D 3.5 Reduce Person clearly say that projectile damage is based on the size of the weapon, not the size of the ammo. If you reduce a human with a bow, arrows shot from the reduced bow do size S damage (from 1d8 to 1d6). If you enlarge a human with a bow, arrows shot from the bow do size L damage (from 1d8 to 2d6). This makes sense.
Under Core Rules Pathfinder, the rules are inconsistent. The Pathfinder Enlarge Person spell specifies that bows enlarged to large size still do medium damage, while the Pathfinder Reduce Person spell specifies that bows reduced to small size deal small size damage.
In PF, a reduced human archer does small size damage because "projectiles deal damage based on the size of the weapon that fired them." This is the same as in D&D3.5.
In PF, however, an enlarged human archer does medium size damage. "Any enlarged item that leaves an enlarged creature's possession (including a projectile or thrown weapon) instantly returns to its normal size. This means that thrown and projectile weapons deal their normal damage."
See the inconsistency? PF Reduce Person says projectile damage is based on weapon size, and PF Enlarge Person says projectile damage is based on ammo size.
I found two threads on the Paizo PF Rules forums on this topic, here in 2011 and here in 2013. Both threads spelled out the problem, but there has been no official remedy or response, except for this: "8 people marked this as FAQ candidate. Staff response: no reply required."
April 2014 Update: Here is yet another thread, still with no satisfying resolution.
Here is my question: It seems clear to me that PF chose to nerf projectile damage while enlarged even though it is inconsistent. This is in a game with the Gravity Bow APG spell, so maybe that makes sense from a balance perspective, even if it is illogical. Do you value game balance over internal consistency? Personally, I want both! My solution: I would never allow the Gravity Bow spell, and I would revert the rules to the D&D 3.5 standard.
Also note that there is a kludgey work-around: a clever player under the current illogical PF rules will obtain a projectile weapon and ammo that is one size too big for him to use. Set that weapon down on the ground, cast Enlarge Person, then pick up the now-apropriately-sized projectile weapon and ammo, and you are good to go, damage-wise.
For more on the APG and splat books generally, read my all splat books are bad screed.
This screed was written here on 23 Aug 2013, but some core ideas were posted on a gaming message board on 21 May 2011. This screed was later updated on 30 Oct 13 and 25 April 14.