FOR THE SHOOTING CHRONY® CHRONOGRAPHS,
MODELS: F-1*, M-1*, ARCHERY* and PAINTBALL-CHRONY*®
as well as the
respective MASTER CHRONY® units for these Models. (*see
(** Please Read These Instructions Carefully
Before Using The Chronograph)
SHOOTING CHRONY INC. assumes
no responsibility, either directly or indirectly, for any action or
consequences of any actions associated with the use of its products.
Chrony® measures the speed of bullets, arrow, shotgun-pellets,
airgun-pellets and paintballs, etc.- from 30/FPS (feet per second) to
7000/FPS and with better than 99.5% accuracy. Your Chrony will go with
you anywhere. Just unfold, mount on a tripod or place on a table, insert
Diffusers (if needed) and shoot in less than 2 minutes. All Chronys
come with a 3 year limited Warranty. The Master Chronys
have the same capabilities as their respective Shooting
Chrony counterparts. In addition to that, the Master
Chronys have a LCD Monitor which brings the LCD (Liquid
Crystal Display) readout right up
to your bench, away from the bullets path.
Gives Numbered Shot Velocities; + Velocity
stays on display until you shoot again; + Uses 9 Volt Alkaline Battery
with 48 hours of continuous use; + Stereo Jack for optional Remote Control
or Chrony Ballistic Printer. The Chrony Ballistic Printer, will also function
as a Remote Control. It prints velocities as you shoot and, on real paper.
When done shooting, press STAT button on Printer and it will print Hi,
Low and Average-velocities, Extreme Spread and Standard Deviation. !!
This information becomes available only if and when the F-1 Chrony is
used together with the Remote Control or the Chrony Ballistic Printer.
!! + Upgrades to Alpha, Beta or Gamma Shooting Chrony or Master Chrony.
and PAINTBALL CHRONY
Same functions as the F-1 Chrony. However,
Stereo Jack is optional. The Archery Chrony comes with the Indoor Shooting
Light Fixture. The Paintball Chrony comes with Splatguard and Gun Cradle.
The Archery and Paintball Chronys can also be used with Rifles, Handguns,
HOW IT WORKS
If it doesn’t unfold, it’s not a
Fig. 1. Closed Chrony.
has two eyes (or photo sensors) located in each of the black plastic
housings at the front and back of the main unit. They are located
under the Twin Lenses at the bottom of these housings and they detect
the passage of a bullet over them by sensing the change in the amount
of light. (They detect a momentary change in light intensity.)
As the bullet passes over the first detector, it trips
a counter, which begins to count very rapidly (much as a super-fast stop
watch). The counter is shut off by the second photo sensor when the bullet
passes over it. The computer in the Chrony then converts this information
into feet per second (FPS) or metres per second (MPS), whichever mode
it was set to work in at the factory. The F-1 Chrony measures in FPS;
the M-1 Chrony measures in MPS.
When used with a Remote Control or
Chrony Printer, the computer inside the F-1
Chrony will, after the first shot, compute all statistical information,
such as Hi(gh), Lo(w),
Av(erage) velocities, Extreme
Spread and Standard Deviation,
following each new shot. The use of our Remote Control or
Chrony Printer gives access to the temporary
working memory, which allows the erasing of part of the data . Only the
Beta and Gamma Chronys have a permanent memory, which allows the unit
to be turned off without losing data.
THE BEST WAY TO LEARN TO USE THE SHOOTING CHRONY
It is best to proceed slowly, safely, and have fun doing it. Getting the
Chrony ready to use is easy.
- First, unfold the unit, making certain that the unit
is FULLY OPEN. The base (such as a tripod) may prevent full opening,
in which case the chronograph will read higher (faster) than true velocities
because the space between the points where the bullet crosses the photocells
is shorter than is the distance for which the unit is calibrated.
- Attach a 9-volt Alkaline Battery to
the short cable inside the front housing and tuck it under the spring.
If it is not an Alkaline battery, the Chrony may not work properly.
With a standard model Chrony, the unit is ready to turn on with the
switch on the face. With a Master Chrony, attach the long telephone
cable into the LCD (Liquid Crystal Display) Monitor and to the inside
terminal of the front black sensor housing of the unit. It is now ready
to be turned ON.
STEPS ON SETUP
|1. The first step is
to set up a safe backstop. Chronographs should never be used without
a safe and certain backstop that stop the projectiles (bullets, shot,
arrows), and prevents ricochets.
Fig. 2. Shooting Chrony, front view
|2. To safeguard the
Chrony and to prevent missing the backstop, any firearm used must
be fired from a good rest. A bench with sandbags is the best type
|3. For the best use of chronographs,
velocity measurements should be combined with target shooting (that
is, you are chronographing the same bullets that are being shot at
the targets). Set up a suitable target against the backstop.
|4. To safeguard the instrument (and
to obtain the best results), the projectile must pass between 6 and
4 inches (15 and 10 cm) directly OVER the Twin Lenses in the black
plastic boxes at the front and back of the chronograph. These are
the chronograph’s "eyes". Attaching pieces of dark-coloured
tape on the guide rods (wire rods) at these heights, will help you
to accurately aim your shots.
5. The Shooting
Area. Every Shooting Chrony and Master Chrony comes
equipped with an adjustable-size, triangular shooting area (actually
an upside down trapezium) from 8"X8" to 14.5"X14.5"
(Fig. 2). All Chronys come equipped with four 9.25" wire rods
as well as four 6.5" wire rods with brass connectors attached.
The 9.25" wire rods are to be inserted at an angle into the outer
holes visible on the black plastic boxes of the unit. On bright, sunny
(blue sky) days, install the white plastic diffusers on top of the
wire rods (to simulate clouds). The photo-sensors are pointed at the
diffusers, which create a white background (clouds or diffusers).
On cloudy days, use wire rods for alignment, but without the diffusers.
6. Chronographs should be at least 10 feet (3 m) from the
muzzle of a high-powered rifle, but can be closer to guns with a lesser
blast. Five feet (1.5 m) is about right for .22 rimfire firearms.
Shotguns should be fired at 5 feet because of the spreading pattern
of the shot and errant wads. Arrows must be clear of the bowstring
before passing over the first "eye".
7. The Chrony may be mounted on a (camera) tripod, or on
any adjustable device having a 1/4 inch by 20 thread that will screw
into the hole on the bottom of the unit. It is also possible to rest
the Chrony on a table, though this is probably the most difficult
type of mounting to adjust properly.
8. With an F-1, or M-1 Master Chrony (Fig. 3), place the
LCD Monitor near you on the bench, well away from muzzle blast.
9. Have a notebook and pen with you to record your results
and to make notes.
STOP! BEFORE YOU FIRE THAT
|A. Be Sure that the
backstop is adequate.
RIFLES: Be aware that the bullet line of travel will
be as much as two inches BELOW the line of sight on scope-sighted
rifles. Adjust upward in order NOT to hit the Chrony. If a bullet
hits the Chrony, the Chrony will be destroyed, and will endanger you
and others because of bullet ricochet and flying parts of the Chrony.
Mark the Wire Rods with tape four inches above the Chrony unit for
open-sighted rifles, and six inches for scope-mounted rifles.
Fig.3. Master Chrony
When shooting sub-sonic ammo, the muzzle blast will get to the Chrony
before the bullet, which may cause erratic numbers. Increase distance
because flying wads may go in any direction, protect the face of the
Chrony by taping a thick piece of clear acrylic over the front of
the unit. The acrylic must not extend above the face. Shooting Chrony
Inc. offers such protection (see Accessories List). NOTE: When shooting
without Diffusers one may substitute soda straws or wooden dowels
for the Wire Rods. Hitting the Wire Rods with a bullet could break
the Sensor Housings, whereas straws and dowels provide a safer sighting
Fig.4. Protective Shields
LOADERS AND OTHER BLACK POWDER FIREARMS: In addition
to protecting the face of the Chrony from wads and patches, you may
cover the slots (eyes) of the photo sensors with strong and clear
tape or Protective Shields (Fig.4) to prevent powder residue from
entering these slots. Glass or clear plastic taped over these slots
may also be used.
ARCHERY: Bow to
Chrony distance should be at least an Arrow’s length. Blunt-tipped
or flat-tipped arrows give more Accurate velocity measurements.
O.K., NOW YOU ARE READY
Until you are familiar with the Chrony, shoot
inexpensive ammo, such as airgun-pellets or .22 rimfire bullets. Doing
so will save you money.
- TURN UNIT
ON. If you purchased the Chrony in the United States,
it will automatically record and read in feet per second (FPS). If you
purchased it in a country that uses the metric system, it will record
and read in metres per second (MPS).
- A F-1 Chrony will display AL with
the flashing symbols on each side. . These flashing symbols indicate
that the unit is working and is ready for use. For units that are set
to read in MPS, the display has a dot between the two letters (e.g.,
A.L) with flashing symbols on each side; without the
dot (e.g., AL) the unit readout is in FPS.
- You cannot change the standard of measure on the F-1
and M-1 Chrony units. The F-1 Chrony will show AL
in FPS and the M-1 Chrony will show A.L
- The F-1 and M-1 Chrony and the respective
Master Chrony units report only the shot number and shot velocity
up to 32 shots. Record on paper each shot number and velocity, as these
units do not have a memory. After the 32nd shot, Ln appears, and the
velocity readout flashes. Shot 33 and all subsequent shots report as
shot 32. To start a new string, turn the Chrony OFF
then ON again.
When chronographing projectiles which display a
velocity reading of less than 1000, the readout will display a Decimal
Point and tenths or tenths and hundredths, e.g., 985.7, 43.69, etc.;
The display will report velocities either in FPS (feet per second)
or MPS (metres per second), depending upon factory default setting.
Fig.5. Indoor Shooting Light
For proper functioning, a light-diffuser and an
incandescent light source must be located above each photo-sensor
window (Fig. 5). The Optional Indoor Shooting Light Fixture enables
owners of the Chrony to pursue indoor use. Neon or other fluorescent
lights cannot be used as a chronograph light source because they
flicker at twice the AC (alternating current) frequency and cause
To get the following information,
requires the use of a Remote Control or Chrony
The push button on the Remote Control is the equivalent of the FU
button (or Function button) on the Chrony Printer.
The F-1 Chrony will provide you with summary data such as Hi,
Lo, Average velocities and the total
number of shots fire. Plus: Extreme Spread, Standard
Deviation as well as numbered shots and retrieval of individual
- Deleting Single Shot:
Press & release the FU button repeatedly
until the desired shot number is displayed (NOT the velocity). Press
& hold the FU button until display flashes. Release button immediately.
The Chrony will automatically adjust the statistics.
- Starting a new String:
Turn your Chrony OFF and the ON again. Or, (if you don’t
want to get up) press & release the FU button until
-Hi- is displayed. Hold the button in until the display
changes to -CL-, then release the button. -Clr-
is now displayed. Press & release the button until the display changes
to -CLS-, then press & hold button in until the
display flashes. Release button immediately.
- Retrieve Information:
Anytime you wish, you may view the data you have produced. To do this,
simply press the FU button, identify the information
you are about to receive, release button and read the information. Repeat
this process for each piece if information shown below.
|What you see on press
||What it means
||What you see on release
||Will always be #1 with the F-1 Chrony;
||velocity of the slowest shot
||velocity of the fastest shot
||Average velocity of all shots
||Hi velocity minus Lo velocity
||Standard deviation of string of shots
|Total number of shots recorded since Chrony was
||The number of shots fired.
|# of last shot fired
||velocity of 10th shot
| # of next to last shot fired
||velocity of 9th shot
etc., etc., repeat until all the shots have been shown,
then -[ ]- appears. This means the end of the data and,
that you are ready to shoot again. If you press the FU
button again, you start the viewing cycle over again. Simply pressing
and releasing the FU button takes you from one piece
of data to the next.. If you wish at any time during the viewing process
to return to the working mode, stop pressing the button and wait 15 seconds.
It returns to the working mode by itself. Sometimes, if you hold the FU
button down for more than two seconds at a time, the unit will go into
a sub-menu. Wait 15 seconds, it will return to normal by itself. When
you think that you may have done something wrong, take your hands off,
and it will go back to normal by itself. Features like this make the Chrony
very forgiving and easy to use.
A) PROBLEM: =Lb=flashing. Cause & Remedy:
Battery is low and must be replaced.
B) PROBLEM: No LCD display. Cause & Remedy:
- No battery: connect battery;
- Unit is not turned on; turn unit -ON-;
- Bad connection: tighten battery snaps;
- Battery is dead: replace battery;
- Battery NOT Alkaline: replace with ALKALINE battery.
C) PROBLEM: No reading after shooting. Cause &
- not using diffusers on blue sky, sunny day; add diffusers;
- using diffusers on a cloudy day; remove diffusers;
- unit too close to muzzle; move unit farther away;
- not shooting directly over photocells; aim more carefully;
- unit not properly aligned with bullet path; realign
rifle to point directly at target; and,
- shooting too early or too late (poor light conditions);
wait for better light, or end chronographing session.
D) Err 1 shows on screen; the first sensor
did not detect the passage of the bullet. This means either that the shot
was not fired directly over the centre of the first sensor, or, that there
are poor light conditions. Be sure that the Chrony is aligned with the
line of fire.
E) Err 2 shows on screen; the second
sensor did not detect the passage of the bullet. Same as above: poor light
or poor alignment.
F) Err 3 through Err 8 shows on screen;
the exact number relates to internal codes, and is of no significance
to the user. May indicate poor light condition. Installation of Diffusers
G) Low velocity reading. Light conditions
not right; try diffusers. You may be shooting during poor light conditions.
H) False reading (usually high); can
result from very strong light, or by operation near electric motors, radar,
powerlines, electric fences, static electricity, radio transmitters, etc.
It may also be caused by the Chrony being too close to the gun’s
muzzle. Remedy: try using diffuser, moving away from electrical interference,
moving unit farther from the muzzle, or all of these.
I) Very high velocity readings: 1) can
result from muzzle blast; move Chrony farther from muzzle; 2) Chrony is
not fully open; check for interference from tripod or base.
J) Dead display in cold weather; replace
battery with a warm battery.
OTHER TIPS AND HINTS
Make allowances for temperature differences between chronographing
your loads and their use in competition. In cold weather, powders burn
more slowly and will produce lower velocities than they will at higher
temperatures. Different altitudes may also affect velocity. Loads developed
which are near maximum velocity during cold weather may produce dangerously
high pressures and be unsafe during hot weather. Always try to match conditions
while chronographing with those conditions you will face when shooting
or hunting. That is, if you hunt in late autumn, do the chronographing
in late fall.
ALWAYS WEAR EYE AND EAR PROTECTION
On sunny days, at certain angles, light may reflect from
the bullet and cancel the bullet’s shadow. Mark the bullets all
the way around with a dark-coloured felt marker if this seems to be happening.
On sunny days, the Chrony may be tilted sideways toward
the sun, so that the Diffusers are between the sun and the photocells.
Be sure that the Chrony unit remains fully open, and that it is perfectly
aligned with the target. Using diffusers on cloudy days may shut out too
Using diffusers on cloudy days is not necessary, since
you have the clouds as a white background for contrast.
Chrony calculates data similar to formulas shown below:
Average (Mean) Velocity
||Where V is velocity and n is the number
|Total all shots in a string
and divide by the number of shots in the string,
e.g., (2990 + 3010 + 2996 + 3004) ÷ 4 = 3000 FPS
Deviation, population, (-Sd-)
Multiply the square
of the average velocity by the number of shots and deduct it from
the sum of the squares of all shot velocities, then divide this
total by the number of shots minus 1, and then take the square root
of this figure.
For example: [(29902 + 30102 +29962 + 30042 - 4 x 30002)
÷ (4-1)]½= 9 FPS
Standard Deviation is a measure of how close each
shot’s velocity will be to the "average" shot. It
is called STANDARD because it is computed in such a way that it
has a standard meaning when compared to the NORMAL CURVE. Nearly
all things we measure fit a normal curve [such as the height of
people, the diameter of (supposedly) identical motor pistons, and
the velocity of (supposedly) identical cartridges]. The NORMAL CURVE
shows that all variables occur more frequently at or near the average,
and less frequently as they deviate further from the average. We
use a STANDARD Deviation measure so that all things we measure can
be compared with each other and to this curve [68% of all things
we measure falls between one standard deviation above or below average,
95.4% falls between two Standard Deviations above and below the
average, and 99.7% falls between three Standard Deviations above
and below the average]. Thus, Standard Deviation is a universal
method in statistics and measurement for dealing with and interpreting
Therefore, if the bullets are traveling at an average
velocity of 3000 feet per second, and there is a Standard Deviation
of 20, then 68% of the shots you fire will fall between 2980 and
3020 fps, and 95.4% will fall between 2960 and 3040 fps. Nearly
all of them (99.7%) will fall between 2940 and 3060 fps.
Since Standard Deviation is the most important information
your chronograph can give you, it is useful to understand the reason
for this. At least ten (10) shots are required to obtain a reliable
average and Standard Deviation. Fewer shots (such as 3 or 5) are
typically "small samples", and are considered unreliable
when measuring anything variable.
||Hi - Lo
|Subtract the slowest shot
from the fastest. For example: 3010 - 2990 = 20 FPS
velocity X Average velocity X Weight
of bullet in grains ÷ 450 240 = _____ft. lbs.
The Chrony reads velocity in feet-per-second
(or metres-per-second) and works in a velocity range from 30 fps to 7000
fps (10 mps to 2134 mps). Operating Temperature range: 32o Fahrenheit
to 110 o Fahrenheit (0 o Celsius to 43 o Celsius), non-condensing. (Ambient
temperature must be above dew-point temperature and not fall below dew-point
temperature while Chrony is being used.) Storage Temperature
range: 14o Fahrenheit to 120o Fahrenheit (-10o Celsius to 50o Celsius)
non-condensing. (Ambient temperature must be above dew-point temperature
and not fall below dew-point temperature where the Chrony is being stored,
unless the Chrony is sealed in an air-tight container.)
Accuracy: 99.5% or better. Displayed velocity will not
differ from actual velocity by more than 1 part in 200, i.e., ±10
fps on a velocity reading of 2000 fps. Typical performance is generally
better, and shot-to-shot repeatability is always more accurate, i.e.,
Reported Mean Instrumental Velocity may differ by as much as 0.5% from
actual mean instrumental velocity, but Standard Deviation calculated from
data gathered with a Chrony will always be closer than 0.5% to
actual Standard Deviation for a string. This is an important fact because
an accurate measurement of a load’s uniformity is of considerably
more importance than is an exact measure of its average velocity.
LCD Display: 0.5" (1.37 cm) high; Weight: 2.5 lbs
Battery life: 48 hours of continuous use. Photo sensors have wide sensitivity
range, and are electronically calibrated to obtain maximum accuracy.
Should you have to return your Chrony because of a malfunction, do not
return it to the Dealer, Distributor or Mail-Order House you bought it
from. It must be returned directly to SHOOTING CHRONY, INC.
residents, please return your CHRONY to:
SHOOTING CHRONY INC.
3840 East Robinson Rd., PMB # 298
Amherst, NY 14228 USA
residents and other Non-U.S.
senders please return your CHRONY to:
SHOOTING CHRONY INC.
2446 Cawthra Rd, Building 1, Unit 10
CANADA, L5A 3K6
Phone: 1-(905) 276-6292; FAX: 1-(905) 276-6295
||If it doesn't unfold, it's
not a Chrony®
|Copyright © 1997-2009
Last updated: July, 2009
Pricing effective: · E. & O. E.