1. AS A WHOLE
The 81-mm Italian mortar Model 35 is a smooth bore,
high-angle fire, muzzle-loading Stokes-Brandt type
weapon. Remarkably similar in construction to the 81-mm
American M1, this mortar is a standard Italian Army weapon.
The following table gives comparative data regarding the two weapons:
||Italian 81-mm Mortar||
||U.S. 81-mm Mortar
|Caliber|| ||81 mm (3.2 in)|| ||81 mm (3.205 in)|
|Total weight in action||135 lbs||136 lbs|
|Weight of barrel||47 lbs||44.5 lbs|
|Weight of bipod||42 lbs||46.5 lbs|
|Weight of base plate||46 lbs||45 lbs|
|Internal length of barrel||46 in||45.55 in|
|Max. range (light bomb) ||4,429 yds||3,288 yds|
|Max. range (heavy bomb) ||1,640 yds||1,275 yds|
|Traverse||150 mils (8°26'15")||180 mils|
|Elevation||40° to 90°||40° to 85°|
|Method of firing||percussion||percussion|
|Practical rate of fire||18 rpm||18 rpm|
The barrel is a. smooth-bored, steel tube fitted with a
hollowed and threaded base cap which in turn is fitted to
the socket in the base plate. The base cap is axially
bored, and is threaded to accommodate the striker. A band
and lifting handle are fastened to the breech end of the barrel.
|Italian 81-mm Mortar|
The bipod consists of tubular steel legs, an elevating
mechanism, and a traversing mechanism. The legs have
spiked feet, and their spread is limited by an adjustable
chain. To absorb shock on the legs during firing, a spring
is linked with the chain. The cross-leveling mechanism
is locked with a locking nut.
The elevating mechanism consists of a vertical screw
operating in a threaded tube. The screw is actuated by a
gear-and-handle mechanism of conventional design.
The traversing mechanism consists of a horizontal screw
operating through a threaded T-yoke, the lower end of
which forms a bearing for the elevating screw. An operating
handle is secured to one end of the traversing screw,
and a sight bracket to the other.
Two shock absorbers are mounted in a housing secured
to the yoke, and are clamped to the barrel with a clamping collar.
3. BASE PLATE
The base plate is rectangular. It has three socket
seats and a carrying handle. This is still another respect
in which it is similar to the American M1.
The elevating quadrant provides for vertical adjustment, from 40 to 90 degrees.
The lateral deflection scale, graduated in conventional
mils from 0 to 6,400, is equipped with a sliding scale beneath
it to facilitate traverse readings. From the definition
of a mil as that angle which at any range subtends 1/1000
of the range, errors in deflection can readily be
estimated and corrected.
Two types of semi-fixed high explosive ammunition,
a heavy and a light bomb, are used in this Italian mortar.
Both are painted gray with an orange nose. Contrary to
American practice, the propelling charge and fuze are not
incorporated in the Italian bombs.
The maximum range of the mortar is 4,429 yard for
the 7.2-pound light bomb, and 1,640 yards for the
15.1-pound heavy projectile. The corresponding American
bombs used with the 81-mm M1 weigh 6.92 pounds and
15.05 pounds, and have maximum ranges of 3,288 yards
and 1,275 yards, respectively.