From the beginning of the Second world war in the United States of America closely followed the fighting in Europe and I must say, doing generally the right conclusions from the experience of others. In particular, did not go unnoticed and the first evidence of the use by German forces self-propelled artillery. In 1940 the Americans launched work on the creation of artillery systems of similar purpose. As in the case of self-propelled tank destroyers (“modelist-Konstruktor” No. 1, 2002), the first versions of ACS, armed with field howitzers, was established on the basis of half-track armored personnel carrier M3. On the first set, the swinging part 75-mm mountain howitzer M1A1 on the second — 105-mm field howitzer М2А1. These machines received the designation T30 T19 NMS and NMS, respectively. The abbreviation NMS stands for Howitzer Motor Carriage, which literally means “the engine crew howitzer”, but in the semantic — self-propelled howitzer.
Neither one nor the other car was not standardized, which explains the presence in their indexes of the letter T, which received only prototypes or prototypes. However, they were found partially fit, and for lack of a better commercialized (released 500 units of T30 and T19 324).
In bulk quantities, these machines produce as the half-track armored vehicle was too unreliable a platform for artillery. And if relatively lightweight 75 mm howitzer was he still “on the shoulder”, then the weight and force of the recoil 105-mm gun he kept with difficulty. However, both self-propelled guns had to do some fighting in the Philippines, North Africa and even in Italy, and everywhere they suffered heavy losses.
Meanwhile, in October 1941, on the initiative of the then commander of the tank troops of the U.S. army of major General Jacob Devers of the firm Baldwin Locomotive was manufactured and sent for testing at the Aberdeen training ground in Maryland two prototypes of the 105-mm self-propelled howitzer using the chassis of the M3 medium tank. The machine was designated T32. In an open top stationary armor the cockpit of a rectangular shape on its standard carriage, including the lower part of the machine and the frame, installed a 105-mm field howitzer М2А1. After testing in Aberdeen in early February 1942, the machine was moved to Fort Knox, where experiments with self-propelled guns continued. The results of tests on the machines have increased armor protection of cuttings, reduced the angle of elevation of the howitzer and mounted anti-aircraft gun. In April 1942, SAU was accepted into service under the designation 105 mm Howitzer Motor Carriage M7. First serial self-propelled guns left the workshops of the company American Locomotive Company in the same month. Production continued until August 1943, when after the release of 2814 machines stopped it. However, in 1944 the production of the M7 resumed again — from March to October, issued 500 self-propelled howitzers. In March 1945, production of the M7 has joined the firm Fédéral Machine and Welder Company, brought together 167 combat vehicles of this type.
Self-propelled howitzer M7:
1 — 105-mm howitzer; 2— 12.7-mm anti-aircraft machine gun; 3 — gear box; 4 — the directing wheel; 5 — support roller; 6 — the driving wheel; 7 — gunner’s seat; 8 — combat pack; 9 — reservation of the turret anti-aircraft machine gun; 10—movable us of a cannon; 11 — cover of the inspection hatch of the driver
The layout of self-propelled howitzer M7B1:
1 — 105-mm howitzer; 2 — 12.7-mm anti-aircraft machine gun; 3 — piling art shots; 4 — oil heater; 5 — radiator; 6 — the fan drive; 7 — engine; 8 — suspended floors; 9 — batteries; 10 — gun carriage; 11 — fan; 12 — the seat of the driver; 13 — levers and foot controls; 14— gear box
Self-propelled howitzer “Sexton”:
1 — 25 pounder howitzer; 2 — sight of the howitzer; 3 — cutting; 4 — radio station No. 19; 5 — coil telephone cable; 6 — covers, tarpaulin; 7 — guide wheel; 8 — driving wheel; 9—boxes of artillery rounds; 10 — a box with radio; 11 — movable reservation; 12 — cover observation of the driver’s hatch
Self-propelled guns early releases were made on the basis of medium tanks M3, which was based on suspension, engine and transmission. Frontal part of the body was assembled from three cast parts, and the right one was lower than the Central and left. This was due to the design features of the hull of the M3, who had a gun sponson on the starboard side. Later cars have already used the chassis of the medium tank M4 “Sherman”, at first also with the frontal part of the three parts (already the same height), connecting with each other and with the housing bolts, and then cast. Casting the bow as a differential case and side gear. Its bolted to the body facilitates the disassembly of the bow for the dismantling of these units and gearbox.
Open top combat tower, welded from flat armor plates with a thickness of 12.7 mm, were located in the middle of the hull. In the embrasure of her front plate was installed 105 mm field howitzer М2А1 with a small mobile booking. Angle horizontal guidance was right 30° left 15°. Vertical guidance is carried out in the range from – 5° to +35°.
ACS early editions had the ammunition, consisting of 57 unitary shots, then, due to the reduction of seated crew members, it was increased to 69 shots. The ammunition load included high explosive, shaped charge, incendiary and smoke shells. Maximum firing range was 10 424 m. the Rate of fire is 8 RDS./min.
Right in front of the conning tower on the turret, mounted on a special turret of cylindrical shape, mounted with 12.7 sanity Browning machine gun М2НВ. Ammunition gun consisted of 300 rounds of ammunition.
Aft ACS with a slight tilt forward, as in the basic tank M3, was mounted 9-cylinder four-stroke radial petrol engine Continental R-975-EC2 air-cooled power 340 HP at 2400 rpm. He allowed a 23-ton vehicle with a maximum speed of 38.6 km/h Capacity of four fuel tanks were 662,4 l, which provides a range of 193 km/h. On the ACS later made on the basis of the medium tank M4 was installed engine Continental R-975-C1 power 350 HP
Transmission of ACS consisted of double-disc main clutch dry friction, mounted inside the flywheel of the engine, propeller shaft, five-speed manual transmission with synchronizers, dual differential type Cletrac and final drives.
In the suspension on each side consists of six rubber-coated rollers are connected in pairs in three tandem suspended on a vertical buffer springs, three rollers, guide wheel with a crank tension mechanism and a driving wheel at the front with a removable ring gear. And on SAU earlier releases support rollers installed on the trucks suspension, as on the tank M3, and on the later machines they were attached to the trolley by means of brackets with an offset back. Caterpillar — rubber-to-metal melkopilchatye cycloid gear 79 tracks each.
By 1944, the standard and most common in the U.S. army version of the tank “Sherman” became М4АЗ. In March 1944 on the chassis of this tank began production of self-propelled howitzers М7В1. From the ACS M7 it differed mainly power unit — 8-cylinder V-shaped petrol engine Ford GAA with 500 HP This motor is dispersed the self-propelled to a maximum speed of 42 km/h otherwise, with the exception of the MTO, the machine almost has not changed. Until February 1945 the factory gate of the company Pressed Steel Car Company went out of 826 self-propelled howitzers М7В1.
The new army artillery began to arrive in 1942, both in American and in the British army. In the past the gunners drew attention to the characteristic shape of the turret for anti-aircraft machine gun that resembled a pulpit, and gave the car the nickname of Priest (“priest” — the priest), soon became its official name. In November 1942 consisting of the 5th regiment Royal horse artillery “priests for some” took part in the battle of El Alamein. Subsequently, until may, 1945, they were widely used by the Americans and British in the fighting in Italy and Northwest Europe. The US army used these self-propelled guns in battles with Japanese troops on the Pacific Islands.
The British converted a number “Bristow” in armored personnel carriers. On the proposal of the commander of the 2nd canadian corps Lieutenant-General G. Symonds in early August 1944 during the attack on Falaise 76 self-propelled artillery M7 was converted to transport infantry. With ACS removed the howitzers and all the internal pieces of artillery, the breach made, and the cutting height increased the armor plates. Of arms remained the only full-time heavy anti-aircraft machine gun on turret. Each of the thus obtained armored Priest Kangaroo (“Kangaroo”) could carry up to 15 Marines. In the army, these armored vehicles are often nazywaj defrocked Priest, that is, “the priest, devoid of spiritual dignity”.
In the postwar period, the M7 self-propelled guns were in service in the US army and several other States. Participated in the war in Korea. And in Korea especially sharply revealed the disadvantage is that the gunners had first noticed in Italy in 1944-1945. We are talking about the inability of this machine, because it is too small for a mortar elevation angle to fire from the reverse slopes of the heights that were fundamentally important in mountainous terrain. In Italy, in order to get out of the situation, the Americans poured an earthen ramp, stopping on which ACS was in a position at an angle of 15-30° to the horizontal. Thus it was possible to increase the angle of elevation of the guns. For Korean front went the other way. On the ACS М7В1 105-mm howitzer mounted in the fighting compartment, so that the maximum elevation reached +65°. This had to significantly increase the height of the line of fire. In turn, we had to build and machine-gun turret, in order to provide the possibility of firing anti-aircraft machine gun on 360°. In this option, the designation М7В2, altered 127 self-propelled guns М7В1. Self-propelled howitzers М7В2 actively used by the U.S. army until the end of the Korean war. In the middle of 1950-ies “priests for some” all modifications have been decommissioned American army.
However, this does not mean the end of their military career, as in many other countries they were operated much longer. For example, the Pakistani troops used “priests for some” during the conflicts with India in 1965 and 1971. During the Arab-Israeli war of 1967, these ACS were used by the IDF. Again see the types of self-propelled guns went into battle in 1973— during the war “judgment day.” This was the last combat actions with their participation.
Already in the process of development of ACS T32 English General staff wanted to get a self-propelled installation armed regular British 25-lb-ing field howitzer Mk II, because the caliber of 105 mm was not standard in the British army. In accordance with 5тим wish in June of 1942 the second prototype SAU T32 established English howitzer. Converted thus the machine received the designation of Kzt51.. She arrived at Aberdeen proving ground for tests, which lasted until the beginning of 1943, when the programme for the development of Kzt51. was discontinued in favor of a similar canadian program. The latter included the installation of 25-pounder howitzer on the chassis of the canadian Ram cruiser tank (“modelist-Konstruktor” No. 1, 2002). The first prototype of such a machine were transferred to the test at the end of 1942. In early 1943 the machine, the designation of 25 pounder Ram Carrier (literally it can be translated as “carrier of the 25-funtouki chassis Ram”) recommended for serial production. The designation was soon changed to a 25 pounder Self-Propelled Gun, Sexton — 25-pound self-propelled artillery gun “Sexton”. “Sexton” in English means “Sexton”. Thus the British continued the tradition of assigning self-propelled howitzers names sootvetstvovala Sanam various Ministers of the Church.
Structurally, the “Sexton” was like the us M7 self-propelled guns. Open top welded rectangular combat tower occupied the Central part of the body. In the cockpit offset to the left from the axis of the machine was set swinging and the upper part of the machine 25-pounder (87,6 mm) howitzers. Lower the machine without the elements of the course and the frame is welded to two traverses of the floor of the conning tower. The recess in the frontal cutting was closed semicircular mobile booking-sponson providing a horizontal traverse 25° left and 15° right. Elevation ranged from – 9° to +40°. Ammunition howitzers consisted of 117 rounds of separate loading, 112 of which were located in boxes under the floor of the fighting compartment and five drawers on the right aft part. For the firing of howitzers used high-explosive, armor-piercing, and smoke shells.
Radial 9-cylinder carbureted engine Continental R975-4 power 484 HP allowed 26-ton-Noah fighting machine to reach the speed of 40 km/h. cruising range was 290 km. the ACS Crew consisted of 6 people.
SAU “Sexton” was produced in two versions. 124 the first machine received the designation “Sexton I”. The ensuing 2026 “Sexton II” based on units of tanks Ram later releases. Outwardly, however, they differed only assembled together with the housing boxes for placing batteries and generator in the rear of the hull. In addition, since the 147th cars, they were equipped with two Bren machine guns intended for self defense and shooting at air targets. Self-propelled “Sexton II” received and 15.5-inch steel canadian melkopilchatye (step truck 117 mm instead of 152 mm in the us) tracks and drive wheels with 17 teeth. “Sexton” on both versions of Pro-isotypes firm Montréal Locomotive Works until the end of 1945.
Self-propelled howitzers “Sexton”, since 1944, has been used in the fighting British, canadian and Polish troops in battles in Italy and Northwest Europe and proved itself as quite successful fighting machine. Armed with the British army they were to the middle of 1950-ies, and in the armies of India, Italy, Portugal and South Africa even longer.
A story about self-propelled howitzer “Sexton” would not be complete without mention of its most known variant created in Australia. Since all attempts to obtain artillery for test and research purposes from the UK were unsuccessful, in July 1949, Australia was given the green light to develop self-propelled howitzer of his own design. I must say that due to the nature of the theater of war, which had to fight Australian troops — the Islands of South-East Asia and the Pacific, by the end of 1940-ies of the Green continent was the reserve frankly outdated armored vehicles. In the Australian army at that time, there were two tank brigades, one equipped with “Matilda”, the other tanks “Grant II” (МЗА5). On the basis of the latest and developed by the Australian self-propelled howitzer. Taking into account that the canadian Ram tank had the same chassis that МЗА5. Therefore, the basis for the Australian project was based on drawings received from Canada.
“Grant” eliminated the turret, the sponson and the upper part of the fighting compartment, and instead, mounted the conning tower, almost identical in construction with the wheelhouse “Sexton”. The armament was a 25-pound howitzer, was also borrowed from the canadian prototype. As a result, the car was externally very similar to the “Sexton”. Sharply conspicuous differences are the doors in the sides of the hull, inherited from the “Grant” and suspension from the “Sherman” which was equipped with all Australian “grants” in 1944. The place of the driver was moved closer to the starboard side, which only added to the similarities with “Sexton”. SAU, like the basic tank, equipped with a diesel engine General Motors 6046 G-71 with a capacity of 375 HP
The first sample was collected in army machine shops in Moneghetti in 1949. Testing of the prototype was conducted at the site in Pukapukara. On their successful completion of a military factory in Bendigo has received an order for 13 combat vehicles. The first production car left the shops in November 1950 and the last in late 1952. Long been some debate about the name of ACS. Officially suggested the name was so cumbersome that it was rejected by the military. In the end, self-propelled howitzer has received the name Yeramba (“arumba” — a device by which the Australian aborigines threw Darts).
New self-propelled gun entered service with the 22nd regiment of the Royal Australian field artillery and its structure was involved in fire support units of the 2nd tank brigade during maneuvers in Puckapunyal. The development of combat vehicles artillery was facilitated by the fact that towed 25-pounder howitzers were the standard weapons of the Australian army and used it until 1962. However, the life of the self-propelled guns was short-lived; in 1956, in Australia, has written off all obsolete equipment—”Matilda”, “grants”, and together with them and “eruby”. Currently, only the tank Museum of the Royal Australian armored corps in Pukapukara is the owner of a complete instance of the self-propelled artillery unit of the Australian design.
M. BARYATINSKY
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