Draw Force Curves

Here is a selection of Cari-bow draw force curves (sometimes called bow force maps).  There are two lines in the charts. The straight line is called the base line, and the second line represents the draw force curve for the individual bow. In the first chart below, the red line is the baseline which helps us see the performance of the bow being tested.

Cari-bow Silver Fox gives a smooth draw beyond 30 inches
This Cari-bow 52 pound Silver Fox gives a smooth draw beyond 30 inches.

Analyzing Bow Performance With  A Draw Force Curve

What would a bow drawing just like the baseline feel like, and what performance would it give?   How does this bow compare to the linear steady slope of the baseline, and how will you see that play out in performance?  These are questions the chart will help us answer.  If a line on the draw force curve is straight (the red line in the chart above), for each inch you draw back, the stored energy increases by a certain rate.

extra energy shown in a draw force curve
The yellow area above the baseline shows the extra energy that is stored in a recurve or reflex-deflex design.

If the curve of the bow climbs upwards at a steeper rate early in the draw, it stores more energy right away. That is overall a good performance trait, if it does not continue to climb at a rate that is too steep. You can see in the Cari-bow draw force curves that after an initial rise, they come back very close to the baseline curve, and remain close there for the remainder of the draw.

How To See Stacking In The Draw Force Curve

Stacking can be seen in the bow force map when the curve of the bow climbs in a steeper fashion, and does not return to the straight baseline curve. The result of stacking is a bow that is not smooth to shoot. For any given effort in the draw, a bow that is stacking sends the arrow at a slower speed, with more hand shock.

A draw in the 30" range or beyond will usually start to show a sharper rise in the draw force curve, but all Cari-bows are built with a limb construction that keeps “stacking” to a minimum. This allows the archer to store energy early in the draw and still have a smooth shooting bow.

 

"Hunting with the Peregrine is like having 5 extra pounds of draw weight that you do not have to pull."  -Pete Ward

Slynx

draw force curve for cari-bow Slynx
54 Inch Slynx Takedown Longbow Draw Force Curve

Tuktu EX

50 lb Cari-bow Tuktu EX DFC
The portion where the Tuktu EX curve raises above the baseline shows the extra power stored early in the draw.

Peregrine

cari-bow peregrine draw force curve
The draw force curve for a 51 pound Cari-bow Peregrine longbow.

Silver Fox

Cari-bow Silver Fox gives a smooth draw beyond 30 inches
This Cari-bow 52 pound Silver Fox gives a smooth draw beyond 30 inches.