After graduating from the school in October 1927, Beylin was appointed to the 80th Light Artillery Regiment of the 80th Rifle Division of the Ukrainian Military District at Artemovsk.

In this position, he fought in defensive battles on the Western Dvina, on the Velikaya on the line of Vybori and Opochka, and on the Lovat in the area of Kholm.

From 14 January 1942, then-Lieutenant Colonel Beylin served as deputy chief of staff of the 4th Shock Army, which fought in the Toropets–Kholm offensive as part of the Kalinin Front.

Then-Colonel Beylin served as temporary corps commander between 29 September and 24 October 1942, leading it in battles in the Nevel sector as part of the 3rd Shock Army.

[2] On 23 September 1943, Beylin took command of the 91st Guards Rifle Division, which he led until being transferred to serve as chief of staff of the 3rd Shock Army on 14 October.

He became a senior instructor in the operational arts department on 14 November 1945, and was transferred to the Kuybyshev Military Engineering Academy in April 1949.