a. General
This machine gun is not dissimilar to the French Hotchkiss, with the exception of the thumb
trigger, like the British Vickers. From the following report, prepared at the Aberdeen
Proving Ground, it appears to be an excellent gun.
The gun is gas-operated, air-cooled and has a quick-change barrel. The cartridges are fed
from plate chargers holding 20 rounds, each round being housed in a separate compartment (see
sketch). After firing, the empty cases, instead of being ejected, are replaced in the
compartment of the plate charger.
The gun uses ammunition very similar to our own with the exception of the case which is
shorter and the caliber which is .015 of an inch larger. It is made in ball, tracer, and
incendiary tracer armorpiercing. The German 7.92-mm ammunition can also be used.
b. Description
Following are characteristics of this gun:
Caliber | | 8 mm (.315 in) |
Weight | | 44 pounds |
Length over-all | | 50 in |
Weight of barrel, complete | | 17-3/4 pounds |
Length of barrel, complete | | 33-1/4 in |
Rifling | | 4 lands, right hand twist |
Rear Sight: | | |
Elevation | | 300 to 3,000 meters |
Windage | | 0 to 8 mils plus or minus (0 to 2-1/4° plus or minus) |
Cyclic rate of fire (maximum) | | 450 rounds per minute* |
Effective rate of fire | | Unknown |
Muzzle velocity | | 2,600 feet per second* |
Maximum range | | 6,500 yards* |
Cooling | | Air |
Mounting | | Tripod |
Feed | | 20-round plate charger |
Provision for single-shot fire | | None |
Safety | | Shift safety catch on top of rear cross-piece to S for "safe" and to F for "fire". |
The accompanying range table covers the Breda Model 37 and also the Fiat Model 35.
c. Tripod Mount
The mounting is provided with elevating and traversing gears, which can be used in conjunction
with the open sights for direct laying, or with the elevating and traverse scales for indirect
laying.
Elevation is adjustable from 360 mils (20 degrees) depression to 360 (20 degrees) elevation, with
a micrometer adjustment from the 46 mils (2 degrees 30 minutes) depression
to 36 mils (2 degrees) elevation.
The main traverse scale is graduated from 450 mils (25 degrees) to 1,150 mils (65 degrees)
in 10 mil steps, the central position being at 800 mils (45 degrees). An additional
150 mils (8 degrees 30 minutes) traverse is provided by an independent micrometer
adjustment.
RANGE TABLES FOR ITALIAN 8-MM MGs--FIAT MODEL 35 AND BREDA MODEL 37,
FIRING MODEL 35 BALL AMMUNITION
|
Range (yds) |
Fiat 35 Elev. (mils) |
Breda 37 Elev. (mils) |
Range (yds) |
Fiat 35 Elev. (mils) |
Breda 37 Elev. (mils) |
Range (yds) |
Fiat 35 Elev. (mils) |
Breda 37 Elev. (mils) |
Range (yds) |
Fiat 35 Elev. (mils) |
Breda 37 Elev. (mils) |
100 | 1 | 1 | 1200 | 19 | 19 | 2300 | 68 | 66 | 3400 | 150 | 148 |
200 | 2 | 2 | 1300 | 22 | 22 | 2400 | 74 | 72 | 3500 | 159 | 158 |
300 | 3 | 3 | 1400 | 25 | 25 | 2500 | 80 | 78 | 3600 | 168 | 168 |
400 | 4 | 4 | 1500 | 29 | 28 | 2600 | 86 | 84 | 3700 | 178 | 179 |
500 | 5 | 5 | 1600 | 33 | 32 | 2700 | 93 | 91 | 3800 | 188 | 190 |
600 | 6 | 6 | 1700 | 37 | 36 | 2800 | 100 | 99 | 3900 | 199 | 202 |
700 | 8 | 8 | 1800 | 41 | 40 | 2900 | 108 | 107 | 4000 | 210 | 214 |
800 | 10 | 10 | 1900 | 46 | 45 | 3000 | 116 | 114 | 4100 | 221 | 226 |
900 | 12 | 12 | 2000 | 51 | 50 | 3100 | 124 | 122 | 4200 | 234 | 239 |
1000 | 14 | 14 | 2100 | 56 | 55 | 3200 | 132 | 130 | 4300 | 247 | 253 |
1100 | 16 | 16 | 2200 | 62 | 60 | 3300 | 141 | 139 | 4400 | 261 | 286 |
|
Standard conditions: barometer 750 mm (29.5 in) of mercury,
temperature 15° C (59° F),
humidity 0.5 (half-saturated air).
|
Comment: The gun is quite simple in its operational features, and is extremely easy
to disassemble. The breech is positively locked at the moment of firing, the breechblock
being forced up (without tilting) by the action of inclined surfaces on the piston
extension, so that a projection on its upper surfaces engages in an opening in the
top of the body. The barrel is sufficiently heavy (17-3/4 pounds) to
enable it to fire a large number of rounds in quick succession without overheating.
*This information has not been checked by U.S. test.