Vortex EBR-1 MOA Reticle
The Vortex Razor HD 5–20x50 riflescope is equipped
with the Vortex EBR-1 MOA reticle.
Designed to maximize
long distance shooting
and ranging abilities,
the EBR-1 reticle can
be used to effectively
determine ranges,
holdovers, and
windage corrections.
Ultra precision laser
etching on the glass
reticle ensures that MOA specifications can be kept
to the tightest tolerances possible. The fine center
crosshair subtensions on the EBR- 1 reticle were
carefully chosen to provide the optimum balance
between precision aiming and low light visibility.
1
MOA Subtensions
The EBR-1 reticle is based on minute-of-angle (MOA)
subtensions. Many shooters
are very familiar with the
MOA system used in hunting
riflescopes. MOA measurements
are based on degrees and
minutes: 360 degrees in a
circle, 60 minutes in a degree
for a total of 21,600 minutes.
These angular measurements
are used to estimate range and
correct for bullet trajectory
drop in riflescopes. 1 MOA will
correspond to 1.05 inches at a 100
yard distance, 2.1 inches at 200
yards, 3.15 inches at 300 yards,
and so on.
Estimating MOA
Although 1 MOA is very
commonly corresponded
to 1 inch at 100 yards,
this is not quite correct
1 MOA at 100 yards
equals 1.05 inches.
Calling 1 MOA an inch
per 100 yards may be
acceptable at shorter
distances, but it will
cause a fi ve percent error
in ranging and holdover
adjustments. This will
result in missed shots at
longer distances.
the shooter does not have to remember to set the scope to
one particular magnification to get valid holdovers—an
action necessary in the more common second focal plane
reticles.
Fine Crosshair
Heavy Crosshair
When used in a first focal plane
riflescope, such as the Vortex Razor HD riflescopes,
the MOA subtensions of the EBR-1 reticle are valid at all
magnification levels. This means the shooter can use the
magnification level most appropriate for the situation and
still have effective holdover and windage reference marks.
This is extremely valuable in a high-stress situation because
23
EBR-1 Reticle Subtensions
2 MOA subtension marks
5 MOA subtension marks
Crosshair thickness
Fine: .2 MOA
Heavy: 5 MOA
Ranging
MOA measurements are very effective for ranging using a
simple formula. To use this formula, the shooter needs to
know the size of the target or nearby object in inches.
MOA Ranging Formula
Example
Target Size (Inches) x 95.5
Measured MOAs
=
Range (Yards)
Using either the vertical or horizontal MOA scale,
place the reticle on a target of known dimensions and
read the number of MOAs spanned. You will obtain
maximum accuracy in ranging by calculating exact MOA
measurements. MOAs should be estimated in 1/4s if
possible. To help calculate fractions of MOAs, the inner
crosshair line thickness can be used as a reference. All
inner line thicknesses subtend 1/5 MOA.
Accurate measuring will depend on a very steady hold. The
rifle should be solidly braced using a rest, bipod or sling
when measuring. Once you have an accurate MOA reading,
use the formula to calculate the distance.
Ranging a 6-foot target stand (72 inches)
at 12 MOAs yields 573 yards.
72 x 95.5
12 MOA
=
573 Yards
Note: In the MOA ranging formula, a shooter may substitute 100 for 95.5
in the interest of speedier calculations. Be aware that this will produce a
fi ve percent over-estimation error of the yardage distance obtained.
45
Elevation Holdovers
Once the distance has been calculated using the EBR-1
reticle or a laser rangefinder, the EBR-1 can be used for
rapid holdover correction for bullet drop of the cartridge
being used. To get the most benefit out of the EBR-1
equipped riflescope, Vortex Optics highly recommends
shooters learn their bullet drop numbers in MOAs rather
than inches.
Since the EBR-1 reticle is scaled in 2 MOA increments,
it is an easy job to quickly select the correct drop
reference line once the shooter knows the bullet drops in
MOAs. If the shooter prefers to dial come ups for bullet
drop using the elevation knob, knowing bullet drops
in MOAs rather than inches will allow for much faster
adjustments as the MOAs can be quickly read on the
elevation knob.
Example
17.5 MOA reticle holdover for 625 yard shot. No wind.
67
Windage and Moving Targets
The EBR-1 reticle is highly effective when used for
wind and moving target leads. Using the reticle
for effective windage and moving target leads will
require thorough knowledge of your weapons
system’s ballistic performance under varying
conditions and experience in reading wind strengths
and target speeds. As in bullet drops, it is important
for the shooter to learn a particular weapon’s
windage/moving target corrections in MOAs rather
than inches. Always hold the reticle into the wind.
Basic windage correction on center crosshair
When dialing elevation come ups, the center
horizontal crosshair will be used for windage
or moving lead corrections. MOA marks on the
horizontal crosshair are graduated in 2 MOA
increments out to 10 MOAs, and at 5 MOA
increments beyond that.
Example
10 mph wind
Full value wind at 90 degrees
3 MOA reticle windage correction for 400 yard shot in 10 mph
crosswind using center crosshair. Elevation adjustment already dialed
into rifl escope.
89
Basic windage correction using drop line on reticle
When using the reticle for elevation correction rather than
dialing, the MOA marks on the center horizontal crosshair
can still be used to help visually reference windage
corrections. Remember to hold the reticle into the wind.
Example
20 mph wind
Full value wind at 90 degrees
Basic moving lead correction
When estimating moving target leads, the MOA marks
on the center horizontal crosshair can be used. Estimating
moving target leads will require knowing yardage distance,
wind speed, moving target speed, and total bullet flight time
(including rifle lock time). Bullet flight times can be roughly
calculated based on fps velocities or a ballistic calculator.
Note: Correctly estimating moving leads is very diffi cult and requires
considerable practice and knowledge beyond the scope of this manual.
Example
Moving Direction
8 MOA reticle windage correction for 500 yard shot in 20 mph
crosswind using 12 MOA reticle drop line.
9.4 MOA reticle correction for a target moving 3 mph at a distance of
800 yards. No wind. Total bullet time of fl ight from trigger pull 1.5
seconds during which the target travels 6.6 feet. Elevation already dialed
into turret.
Vortex Service and Repair Policy
Unconditional Lifetime Warranty
Vortex Optics wants you to shoot
and use your Razor HD riflescope
under any conditions with
complete confidence—that’s why
our warranty is straightforward
and simple:
Unconditional Lifetime
• Fully transferable
Warranty
• No warranty card needed
• No receipt needed
Rest assured, if this riflescope should ever require repair, all
you need to do is contact Vortex for absolutely free service.
Call 800-426-0048 or e-mail service@vortexoptics.com.
Vor tex Optic s
2120 West Greenview Drive
Middleton, Wisconsin 53562
USA
vortexoptics.com
Patent Pending
Dual Use for Shooting Tactical / Hunting
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