100 mm field gun M1944 (BS-3)

The 100 mm field gun M1944 (BS-3) (100-мм полевая пушка обр. 1944 г. (БС-3)) is a Soviet 100 mm anti-tank and field gun.

Development
The BS-3 was based on the B-34 naval gun. The development team was led by V. G. Grabin.

World War II
During World War II the Soviet Army employed the gun in the light artillery brigades of tank armies (20 pieces along with 48 ZiS-3) and by corps artillery. In the Second World War the BS-3 was successfully used as a powerful anti-tank gun. It was capable of defeating any contemporary tank at long range, excluding the Tiger II: to destroy that heavy tank the gun needed to shoot at less than 1600 m from the target. The gun was capable of defeating the turret of Tiger II at a range of 800–1000 meters. The gun was also used as a field gun. Though in this role it was less powerful than the 122 mm A-19, as it fired a smaller round, the BS-3 was more mobile and had a higher rate of fire.

Post World War II
The BS-3 remained in service into the 1950s. As of 1955 it was getting replaced in Soviet service by the T-12 antitank gun and the 85 mm antitank gun D-48. A number of BS-3 pieces are still stored in Russian Ground Forces arsenals. In 2012, at least 12 BS-3 guns were still active with the 18th Machine Gun Artillery Division, located on the Kuril Islands, used as anti-ship and anti-landing guns.

During the Russo-Ukrainian War (2014-present) both sides employed towed anti-tank guns. The use of the 100 mm Rapira is well known, but the Ukrainian Army also used the older BS-3. Three Ukrainian BS-3s were destroyed by Russian military forces during the initial phase of their 2022 invasion of Ukraine. In September 2023, Ukraine's State Border Guard Service released footage of a Ukrainian BS-3 crew firing on Russian positions.

Ammunition data

 * Ammunition
 * AP: BR-412
 * APBC: BR-412B, BR-412D
 * HE/Fragmentation
 * Projectile weight
 * AP/APBC: 15.88 kg (35 lbs)
 * HE/Fragmentation: 15.6 kg (34.39 lbs)
 * Armor penetration (BR-412B, 30° degrees)
 * 500 m : 190 mm (547 yds : 6.29 in)
 * 1000 m : 170 mm (1,093 yds : 6 in)

Operators

 * Republic of the Congo: 10
 * Democratic Republic of the Congo
 * 🇨🇾 Cyprus: 10-20
 * 🇪🇹 Ethiopia
 * 🇮🇳 India: 350
 * 🇰🇬 Kyrgyzstan: 18
 * 🇲🇱 Mali: 6
 * 🇲🇳 Mongolia: 45
 * 🇲🇿 Mozambique: 20
 * 🇳🇮 Nicaragua: 24
 * 🇰🇵 North Korea: 500
 * 🇸🇩 Sudan: 20
 * Syria: 300
 * Timor-Leste
 * 🇺🇦 Ukraine: Reactivated during the 2022 Russian invasion of Ukraine.
 * Vietnam: 250
 * 🇾🇪 Yemen: 20

Former operators

 * undefined: 250
 * East Germany: 144
 * 🇪🇬 Egypt: 100
 * 🇸🇴 Somalia: 35
 * Soviet Union