Each row is one complete bow-and-arrow setup. Edit the essential numbers inline, expand a row
for preset loaders and bow math, and the graphs update automatically for every build in the
bench.
Active Build
278.8 fps
72.0 ft-lb · 0.516 momentum
Best Margin
+7.0 ft-lb
Build 1 against the 65.0 ft-lb target
Target Speed
265.0 fps
416.8 gr at the active row
Required Grains
325 gr
At 300 fps to hit 65.0 ft-lb
Build Bench
One row per setup
Inline controls stay focused on the essentials. Open details only when you need preset
loaders, bow fit math, or speed-model controls.
Launch speed
Chrono anchor
KE72.0
Margin+7.0
Hold10.4 lb
FOC16.3%
GPP6.04
gr/in14.37
Components173.2 gr
ModeComponent
Bow Loader
Choose a bow preset
Current selectionHoyt Carbon RX-9 342 IBO · 30.5 in ATA · prior flagship
342 IBO · 30.5 in ATA · prior flagship
342 ATA30.5 in ATA6.13 in brace25-30 in
296.1 fps bow estimate
Published speed is anchored at 30 in /
70 lb /
350 gr.
ΔDL -22.5ΔDW -2.0ΔArrow -21.4Ideal fit at 27.5 in inside the 25.0-30.0 in range.
Arrow Loader
Choose a shaft preset
Current selectionEaston 5.0 300 5 mm hunting shaft · 8.4 gpi
5 mm hunting shaft · 8.4 gpi
Spine 3008.4 gpi32.5 in stock243.6 gr shaft-only at current length
Arrow Build
Finished mass and FOC
Weight mode
Finished total416.8 gr
Shaft weight243.6 gr
Components173.2 gr
FOC16.3%
Launch Controls
Let-off and speed mode
Let-off
278.8 fps resolved speed
Known speed keeps the measured chrono number as an anchor, then adjusts it by draw weight,
draw length, and finished arrow mass. Calculated speed uses the loaded bow preset plus
the same draw and mass adjustments with the global bias trim from Advanced.
Holding weight 10.4 lbMeasured anchor
Launch speed vs finished arrow weight
Every build row projects its own speed curve from its own measured or calculated anchor. Markers show each row’s current finished-arrow point.
Y · fpsX · grains
Kinetic energy vs finished arrow weight
The dashed line is the current target threshold from Advanced settings.
Y · ft-lbX · grains
Arrow path over distance
Path is re-referenced to 100 yd, so the chart answers how far above or below your aim point the arrow rides before that reference. BC 0.230 · 20 yd zero · 2.75 in sight height.
Y · inchesX · yards
Retained speed over distance
Projected retained FPS from 20 to 100 yards. BC 0.230 · 20 yd zero · 2.75 in sight height.
Y · fpsX · yards
Retained kinetic energy over distance
Each line shows how launch energy decays downrange under the same drag model. BC 0.230 · 20 yd zero · 2.75 in sight height.
Y · ft-lbX · yards
Field manual Launch math, target math, and downrange math.
Launch speed
Known speed
v = chrono anchor + Δdraw length + Δdraw weight - Δarrow mass
If you know the actual chrono number, the app stores the whole measured build as an
anchor. Changing draw weight, draw length, or finished mass moves away from that anchor
using the same sensitivity model as the bow database.
Calculated speed
v = published speed + Δdraw length + Δdraw weight - Δarrow mass + bias
The bow preset provides the published speed anchor and rating conditions. Your row then
adjusts away from that anchor using the global sensitivity values in Advanced. Let-off
does not add launch speed here; it changes holding weight.
Target margin is simply the build’s kinetic energy minus the configured target energy.
Positive means the build clears the goal. FOC is estimated from the balance point of the
shaft, point, insert, collar, nock, vanes, wrap, and any front or rear accessories.
Arrow path and retention
Path = launch angle - gravity drop - sight height
The app first solves a launch angle that zeroes the sight at the configured zero distance,
then re-references the path curve at the chosen path-reference yardage so the chart reads
more like holdover.
Retained speed and retained energy use the same ballistic-coefficient drag model from
Advanced, evaluated every 5 yards from 20 to 100.