Pedestal reference index rationale
RESTRICTED
hair or the latter will drift off the
target.
b. Test may be made with tilt in optics
because regardless of the amount of tilt,
this re
lationship between the plane of mirror rotation
of rotation of the fore and
aft
cross hair remains exactly the same.
Synchronize the Trail Arm With the Cross Trail
Mechanism.
1.
PURPOSE: To have the eccentric stud pos-
itioned
at exact center of the sight stem
with
the trail arm
resting
at zero mils.
a.
When the trail arm is positioned, trail
is set in the trail mechanism and the cross
trail
mechanism.
The trail arm is set off from zero.
but trail in the C.T. mechanism will not be set
in from zero unless the eccentric stud is centered
when the trail arm is at zero.
When the sight stem locking pin is
removed and the sight stem rotated, no tilt in the
optics will occur if the eccentric
stud is center-
ed.
E.
Align Dovetail Parallel to Fore and Aft Axis
of Stabilizer.
1.
The dovetail must be aligned parallel to
fore
and aft axis of stabilizer or, else with zero
drift (no cross wind) there will be a cross trail
tilt of the optics occasioning a deflection error.
2.
When
the dovetail is aligned, with zero
drift, moving the eccentric stud backward and for-
ward does
cause any tilt in
the optics.
The
optics will tilt
if the dovetail is misaligned or
zero drift is not present AND if trail is set
i n
the C.T. mechanism.
F.
Precision Level.
1.
The precision level consists of two parts,
capable (by
turret nut adjustment) of changing
their
relationship to each other.
The component
parts
are
the glass tube, containing the liquid
and
bubble,
adjusting nuts
and the base.
The level has been properly leveled when
the
base
is perfectly. paralled
to the glass.
The procedure
to accomplish this
is to
place a 3-legged precision table on a 3-legged
adjustable table,
and
then the level upon
the
3 - legged
precision table.
The
thumb screws of
the adjustable table are rotated until the bubble
is centered.
Now two
things are true: (1) The
perfectly horizontal and (2) insofar as
not, it has
exactiy the same amount,
opposite error in
it as has the adjustable
table. Turning the precesion level 180° is a means of
and
the
plane
D.
not
the
2.
3.
is
the
base
is
200