As barrel rifling and efficient recoil and breech mechanisms became widely accepted, national armies began development and adoption of 35mm and larger artillery systems - anti-tank guns, field guns and howitzers. The Russian Empire - reincarnated as the Soviet Union following the Bolshevik uprising and subsequent political, social and military victories during and after World War 1 - proved no exception. During the interwar years, several designs were kept on hand until necessity in World War 2 - brought about by the German invasion of the Soviet Union - spurred hasty development of new and more powerful field weapons.
Though warnings were relayed to Soviet leader Josef Stalin, they were disregarded until his nation was steamrolled by German-led Axis forces in June of 1941 through "Operation Barbarossa". The Soviet Army fought to the death, retreated, or surrendered in droves and were largely ill-equipped and ill-prepared for the Axis onslaught. Only stretched supply lines, Soviet determination in a few key quarters and the onset of the Russian Winter slowed the advance outside of Moscow. This lull in the fighting allowed the Soviets to reallocate and recoup resources and men to the front while reestablishing its powerful industrial base in the east.
To provide Red Army artillerymen with a capable long-range weapon of considerable hitting firepower, F.F. Petrov led design work (initially as a private venture designed to shore up the limitation of mobile artillery pieces in the modern Red Army) on a new howitzer based on the barrel assembly of the 152mm M1938 (M-10) coupled to the wheeled carriage of the 122mm M1938 (M-30). The end result was the 152mm M1943 (D-1) which, after being brought to the attention of Soviet officials, was in trials by the middle of 1943 and quickly adopted for frontline service to see extensive use throughout the conflict. Its use of existing components allowed the weapon to be manufactured en mass and rather quickly, doing away with a protracted and expensive developmental cycle common to "all-new" artillery designs. Production was led by No. 9 Plant (Uralmash) based in Yekaterinburg, Russia, and numbered 2,827 examples of which hundreds were in circulation by the end of the war (peaking in 1945 with 715 alone produced - wartime production being 1,057 units). Production spanned into 1949 and operators went on to include many Soviet-allied nations and states. Amazingly, the D-1 continues operational service with several ground forces today (2012).
Design of the D-1 was conventional, essentially a heavy-duty barrel assembly fitted to a support mounting atop a two-wheeled carriage unit. The barrel measured 13.9 feet in overall length and was specifically of 152.4mm (6in) in caliber (generally rounded down in "152mm" in publication) while being capped by a large double-baffled muzzle brake. The mounting system fitted a limited-protection angled shield for point defense of the gunnery crew as well as the requisite recoil facilities identified over-and-under the barrel base. As can be expected, the firing action was a very violent one, requiring the use of such dampeners for obvious reasons. The carriage was of a "split trail" type with tow arms that opened and lowered to act as "legs" in assisting ground placement and further countering recoil. The wheels were solid steel lined with rubber tires which allowed for good off-road travel. Transport was generally by any vehicle available - a heavy duty military-grade truck would suffice as would an artillery tractor. The breech mechanism consisted of an interrupted screw which was hinged to open to the right, allowing a projectile to be fitted into the now-exposed breech. The recoil system was hydropneumatic in nature and highly suitable for the role. The mounting installation seating the barrel allowed for an elevation of -3 to +64 degrees and traversal was limited to +/-17.5 degrees. A trained gunnery crew - optimally made up of 8 personnel, each charged with a certain role in the firing process - could fire off 3 to 4 rounds per minute out to 7.7 miles at a muzzle velocity of 1,600 feet per second. This allowed for excellent range in engaging all manner of targets, particularly dug-in enemy troop positions and fortifications. Overall weight of the system was 8,000lbs which points to the need for multiple crew and vehicles to transport the weapon.
The D-1 was cleared to fire a primary High-Explosive (HE) projectile weighing some 88lbs. Various HE payloads were devised including HE-FRAG to counter steel targets and a time-delay shrapnel round (featuring up to 700 steel metal balls to shred exposed troops). There was also an illumination round for lighting up the night sky during low-light offensives and several lethal chemical shells was added to inventory. Fortifications could be dealt with through use of an anti-concrete projectile that ranged out to 12,400 meters. A HEAT (High-Explosive, Anti-Tank) projectile could be used against armored targets at range while a navalized Armor-Piercing (AP) variant rounded out the available munition options.
In practice, Russian ingenuity prevailed as the D-1 series came as a nasty shock to the Axis armies during the Soviet counter-offensives to follow. Whole batteries of D-1 weapons would precede a large-scale maneuver and lay waste to the ground before the main fighting force to which then the crew could switch to a support role. Wherever and whenever possible, D-1 guns were fielded across the many fronts having been developed by the fracturing of Axis and Soviet forces alike. Soviet artillerymen recalled the weapon as a very reliable system and accuracy at range was only as good as the gunnery crew itself as the weapon in no way impeded their success. The D-1, therefore, remained in wide circulation through to the end of the war and went on to see service in lesser conflicts emerging throughout the Cold War that followed the events of 1945.
Due to the Soviet sphere of influence, the D-1 found a home in many Soviet-allied nations, primarily in Europe, Asia, the Middle East and Africa. It saw action the Arab-Israeli War beginning in 1948 as well as more localized firefights that resolved after the disbanding of the Soviet Empire in 1991. The D-1 still maintains a frontline presence in the fledgling militaries of Afghanistan and Iraq while it remains a centerpiece solution for the modern armies of China, Syria and Vietnam as well as Albania, Cuba and Hungary.