Very scientific after effects frame counting makes me say longbow is about 20%-30% faster. If the games physics are even slightly smartly coded then the fact that javelin drops faster than longbows arrow should also be pretty good indication.
Edit: Now that I’m actually checking this more thoroughly, its really hard to determine when the projectile actually spawns, so depending on how I want to calculate this it could be even 40-50% slower but the projectile is definitely slower. 20-33% seems good median on the stuff I’ve been doing.