You need at least two hands to use a bow, regardless of its size. You can use a composite shortbow while mounted. Composite bows are made from laminated horn, wood or bone and built with a recurve, meaning that the bow remains bow-shaped even when unstrung. All composite bows are made with a particular strength rating (that is, each requires a minimum Strength modifier to use with proficiency). If your Strength bonus is lower than the strength rating of the composite bow, you can’t effectively use it, so you take a -2 penalty on attacks with it. The default composite shortbow requires a Strength modifier of +0 or higher to use with proficiency. A composite shortbow can be made with a high strength rating (representing an especially heavy pull) to take advantage of an above-average Strength score; this feature allows you to add your Strength bonus to damage, up to the maximum bonus indicated for the bow. Each point of Strength bonus granted by the bow adds 75 gp to its cost. For instance, a composite shortbow (+1 Str bonus) costs 150 gp, while a composite shortbow (+4 Str bonus) costs 375 gp.
For example, Tordek has a +2 Strength bonus. With a regular composite shortbow, he gets no modifier on damage rolls. For 150 gp, he can buy a composite shortbow (+1 Str bonus), which lets him add +1 to his damage rolls. For 225 gp, he can buy one that lets him add his entire +2 Strength bonus. Even if he paid 300 gp for a composite shortbow (+3 Str bonus), he would still get only a +2 bonus on damage rolls and takes a -2 penalty to use it because his Strength is insufficient to use the weapon to best advantage. The bow can’t grant him a higher bonus than he already has.
For purposes of weapon proficiency and similar feats, a composite shortbow is treated as if it were a shortbow. Thus, if you have Weapon Focus (Shortbow), that feat applies both to shortbows and composite shortbows.
| Range | Damage | ||||||
|---|---|---|---|---|---|---|---|
| Weight | Cost | Damage | Critical | Increment | Type | Special | |
| Shortbow, Composite | 2 lb. | 75 gp | 1d6 | ×3 | 70 ft. | Piercing |
Source: Player’s Handbook (Page 120)