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Mounting the scope
Your rifle may already be drilled and tapped for the scope
blocks. The hole spacing on our scope blocks were designed
to match that of the Unertl blocks so that they are
interchangeable. If your rifle is equipped with Unertl
mounts and the spacing is correct for your MVA scope, you
need to at least change the front scope block. The Unertl
front block is too short to use with the MVA front mount.
The MVA scope blocks are designed to be mounted on either
round or flat barrels.
If your barrel is not already drilled for scope mounts,
there are some things you need to consider before doing so.
The first consideration is your eye relief (distance between
the eyepiece lens and your eye). The scope has close to two
inches of eye relief, which is sufficient for eyeglasses to
be worn while shooting. The main factor in deciding where on
the rifle to position the scope is where the front mount
must be in order to place the scope close to your eye wile
in the shooting position.
The best way to set this up is to have someone help you.
First, position the front mount about one inch from the
objective bell of the scope and slide the rear mount forward
to about the middle of the scope. Then, get yourself into a
comfortable shooting position, preferably sitting at a bench
with the rifle on a rest. Now have your helper set the scope
on top of the rifle and move it back and forth until you can
obtain the optimum sight picture through it without changing
position. The position of your front mount at this time is
where it needs to be mounted. If, by chance, this procedure
places your front mount right at the transition of your
barrel from octagon to round, you may have the mount along
the Pope rib the distance required to place it on one
surface or the other.
As sated earlier, the front mount placement is limited by
your eye relief at a comfortable shooting position. The
placement of your rear mount, however, is determined by you.
A rule of thumb regarding this decision is that the farther
apart your mounts are, the finer the adjustment is, but the
result is a decrease in total elevation change available in
the mounts. To see a chart of elevation change, in inches,
required to move your point of impact one minute of angle
(MOA) depending on your sight radius (distance from center
of front mount to center of rear mount), click here (will
open in a separate window). The graduations around the base
of the elevation adjustment knob on the rear mount represent
.001" movement per tick mark. The rear mount has a total of
.650" of elevation change available from top to bottom.
As an example of how to read the chart and what it means to
the shooter, if your mounts are spaced 7.00 inches apart,
moving your elevation knob two tick marks (.002") would
change your point of impact one MOA. Therefore, the
elevation change from the bottom position of the rear mount
to the top would envelope 325 MOA, or about 5.4 degrees.
On the other extreme, if your mounts are spaced 21.00 inches
apart, it would require traversing six tick marks on the
elevation knob to move one MOA, as it requires .0061" and
each tick mark is .001". This would then change your total
elevation adjustments to 108 MOA, or about 1.8 degrees.
Depending on the individual rifle and loads being used, the
longer spacing may limit the ultimate range you will be able
to shoot.
On the 23" scope, mount spacing may vary from 7.00" to
12.00" at the extremes. When deciding what spacing will work
best for you, refer to the chart and see what spacing gives
easy adjustment. For example, 10.312" (10-5/16") spacing
will give you .003" elevation per MOA. This equates to three
tick marks on the elevation knob, which may be easier to use
than the .0035" that comes at 12.00" spacing.
When drilling and tapping the barrel for the scope blocks,
make sure the barrel is level and the mounts are centered on
the barrel. The screws for the blocks are a 6-48 threat and
at least .140" of complete threads are required in the
barrel for them to bottom in the blocks. The hole spacing
for the rear block is 7/8" and for the front is 9/16". If
you are at all uncomfortable with this operation, you should
have a gunsmith perform it rather than take the chance of
ruining your rifle barrel.
Using your Malcolm style mounts
The Malcolm style mounts are designed after the original
Malcolm mounts, but a few changes were incorporated to make
operating them easier. These mounts are precision made on
CNC milling machines and lathes to extremely tight
tolerances and, with proper care, will provide you with very
precise adjustment.
You may notice very slight backlash in the threaded
adjustments, but this is necessary for any threads to ensure
that they do not bind up during operation. As long as any
adjustments made are in the same direction of rotation of
the screw, there will be no correction required for the
backlash. If your correction requires going from one
direction of rotation to the other, the technique for
eliminating backlash is fairly simple.
 By
observing where your point of impact occurred, you should be
able to judge the amount of elevation change that is
required. Before changing the elevation, not the position of
the elevation slide in regards to the tick marks on the
sight. Next, observe where the tick marks will line up after
the elevation change. If you are changing rotation of the
screw and you go straight to that point, the backlash in the
threads will be incorporated into the motion. This will
cause your move to be .001" maximum off from what you want
it to be. To eliminate this, move the slide past the mark
you want to go to, then reverse the rotation and come back
to the mark. This will eliminate the backlash from the move
and put you exactly where you want to be.
Before adjusting the elevation on the rear mount, loosen the
large, knurled knob on the left side of the mount. This
allows the elevation to slide freely. Once your adjustment
is made, retighten the knob. Failure to do so may allow the
elevation slide to pivot under recoil and prevent the scope
from sliding through the mounts. Eye injury could be
possible if this happens.
The front mount also has windage adjustment. This is more of
a course adjustment and is used to zero the scope after
mounting it or when wind conditions are exceptionally bad.
Each tick mark on the screws represents .005" and is treated
the same as rear movements for your sight radius. To adjust
the front mount to the left, loosen the left thumbscrew a
few revolutions. Tightening the right screw will then push
the slide to the left. When you achieve the desired
position, retighten the left screw. Going to the right is
the reverse of this procedure.
When shooting the rifle, the scope will slide forward under
recoil. When the scope is first mounted to the rifle, you
should set your battery stop. This is the clamp in front of
the front mount. To do this, slide the scope in the mounts
until the eye relieve is comfortable. Then, while holding
the scope from moving, loosen the thumbscrew on the battery
stop and slide it up against the face of the front mount.
Now retighten the thumbscrew. After firing the rifle, you
can pull the scope back until the stop contacts the front
mount and be ready to fire again.
Adjusting the scope for parallax
Parallax occurs in a telescope when both the target and
eyepiece are not focused exactly on the reticle. When there
is parallax present, moving the eye across the field of view
in the scope will cause the reticle to move across the
target. The movement is very slight and probably not
noticeable without the rifle on a rest, but the associated
loss of precision is drastic when shooting long ranges.
Parallax may be avoided by first adjusting the eyepiece and
them focusing for range. Two steps are necessary because the
human eye's ability to refocus quickly can cause errors in
parallax adjustment. Apparent sharpness of reticle and
target does not alone ensure correct parallax adjustment;
please follow the procedure below.
Adjusting the reticle for level
Once the scope is mounted to the rifle, the reticle may not
be perfectly level with the view. To adjust this, place your
rifle on a rest, or in a vise that will hold the barrel
level horizontally. If the reticle is out of level, loosen
the two screws in the sleeve close to the eyepiece. Again,
DO NOT back them all the way out. This sleeve also
has o-rings in it. Once the screws are loose, rotate the
ring until the reticle is level to the target.
At this time, the scope should be properly adjusted and
ready to use. If you have problems with your groupings,
check for parallax. As stated before, this can be seen by
placing the rifle on a rest with the scope focused on an
object in the distance. Without touching the rifle, move
your eye around the scope's field of view and watch the
reticle in regards to the object in focus. The reticle
should stay on the same spot on the object no matter how you
move. If it does not, repeat the adjustments in these
directions.
Focusing for range
The range adjustment is the knurled sleeve held by two
screws near the rib. After adjusting the scope so that the
reticle is in focus, you will need to adjust the scope to
bring the target into focus. To do this, loosen the two
screws in the sleeve. DO NOT back them all the way
out. The sleeve has two o-rings inside to help seal out
moisture, so the motion will seem a little stiff. Twisting
the sleeve clockwise (as viewed from the eyepiece end) will
move the sleeve away from the eyepiece and bring the focus
towards closer objects. As you look through the scope, twist
the sleeve back and forth until the target comes into sharp
focus. Once focused, tighten the two screws to prevent it
from moving.
Removing the scope and mounts
While the scope blocks are meant to be attached permanently
to the rifle barrel, the mounts themselves were designed to
be easily removable for shooting with iron sights. This is
accomplished by loosening the two screws on the left side of
each mount and sliding both mounts at the same time off of
the scope blocks. Beneath these screws are small brass locks
which may bind a little. If the mounts do no loosen with the
screws, try pushing on the side of the mounts that have the
screws. This should push the brass locks back and free the
mounts.
To reinstall the mounts, slide them over the blocks at the
same time. The blocks are the same length as the mount
bases, so line the ends of them up to achieve the same
position each time. To lock them down, tighten the screws.
DO NOT over tighten, as this will destroy the brass
locks and make it difficult to remove the mounts. The brass
holds well and not much pressure is needed to lock them
down.
Adjusting the eyepiece
When the scope is assembled, the eyepiece is positioned so
that the lock ring is close to .250" from the end thread on
the scope tube (see diagrams below). This is where the lens
should be in an ideal world. Due to manufacturing variation
and the differences in the human eye, there may be some
adjustment necessary for each individual. To make this
adjustment, look through the scope at the clear sky. If
possible keep both eyes open, one on the eyepiece, the other
focused on a cloud. This focuses both eyes at infinity. At
this time, the reticle should be in sharp focus instantly
for your eye. If it is not, loosen the lock ring and rotate
the eyepiece in or out until the reticle comes into focus as
soon as you look into the scope. When this is achieved, lock
the eyepiece with the lock ring to prevent movement. This
adjustment should only need to be done once and not changed
unless your eyesight changes.
Maintenance of scope and mounts
Dirt and moisture are the biggest enemies of a scope. The
MVA scope has safeguards against them both, but excess of
either may damage the mechanism or the optics. ANY
DISASSEMBLY OF THE SCOPE OR MOUNTS WILL VOID THE WARRANTY.
If the assembly gets dirty, wipe it clean. Do no oil the
scope as it may leach into the scope and coat the optics.
Keeping the scope dry will prevent rust. You may choose to
apply a small amount of grease to the contact points between
the scope and mounts to help it slide easier, but this may
allow dirt to accumulate in these areas.
The lenses in the scope are coated to help light
transmittal. If the eyepiece lens becomes dirty, use only a
quality glass cleaner and soft cloth to clean it. DO NOT RUB
DIRT OFF WITH A DRY CLOTH. This will scratch the coating.
The objective end of the scope has a plain glass cover lens
that is easily replaceable if it becomes scratched. Clean
this lens with glass cleaner also. Always replace the lens
caps when not using the scope to protect the outside lenses.
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