Straight-Limb Bows
Advantages
Inexpensive,
can be fitted for both right-handers or left-handers
Disadvantages
Little
cast, Not center-shot
The
straight-limb fiberglass bow is inexpensive, and the same bow can be used by
both right-handed and left-handed shooters. However, the straight-limb design
does not provide very much leverage when the limbs are bent by your pulling
back the bowstring. The arrow sits to the right or left of center of a straight-limb
bow, and you must compensate for this when aiming.
Recurve Bows
Advantages
Greater
cast, Greater arrow speed, Interchangeable limbs if take-down style
Disadvantages
Shooting
for distance requires high draw weight
The
recurved-limb design is the most efficient one. A recurve bow has limb tips that are bent back away from you
in its relaxed position. The bowstring
lies across 2-3 inches of the limb. Yet, when the string is drawn back the
curves straighten to provide leverage when the string is released and the curves
return to their C-shape. This imparts more arrow speed than a straight limb.
The length of the limbs is fitted for an archer's size to maximize the leverage
provided by the limbs. This quality is called cast.
Compound Bows
Advantages
Holding
weight is less than draw weight, Potentially faster
arrow speed
Disadvantages
Must
be fitted for archer's draw length
Compound
bows are characterized by an eccentric, or off-center, pulley or cam mounted on
each limb tip (see Figure £.3). The energy required to rotate the part of the
pulley with the long radius is greater than the energy required to rotate the
part with the short radius. The pulleys
are mounted so that the energy required to pull back the bowstring is the greatest
at mid-draw and the smallest at full draw, when the archer is holding to aim. When the string is released, this situation is
reversed and the energy applied to the arrow is actually increased. For
example, an archer with a 40-pound compound bow of 50% let-off, or reduction,
holds only 20 pounds of resistance at full draw; 40 pounds of thrust, however,
are imparted to the arrow.
