Battle of the Seelow Heights
The Br-2 (or possibly B-30) saw combat in the Winter War against Finland, one piece was lost. As of June 1941, the RKKA possessed 37 or 38 pieces, of them 24 in the aforementioned heavy artillery regiment and further four in two independent batteries. These batteries were given to the Arkhangelsk military district for use as coastal artillery. The rest of the guns, mainly early production guns with shallow rifling and experimental pieces, remained in storage depots and proving grounds. There is only a fragmentary information of the actual combat use of the Br-2. Some sources mention the guns being used in the Battle of Kursk; the 8th Guards Army employed them in the Battle of the Seelow Heights. By the end of the war, Reserve of the Main Command still had 28 pieces, so apparently none were lost.