"April 13th, 1939
To: Director of the Kirov factory, comrade Zaltsmann
CC: Military Representative of the AU at the Kirov Factory, Military Engineer 2nd Grade Buglak
Work on producing an experimental prototype of a tank gun 30 calibers in length is, for some unknown reason, lagging behind all reasonable timeframes, despite being a relatively simple job.
The L-11 prototype presented to the AU was not built according to my specifications, both in design and materials.
I ask to inform me of the reason for your negligent treatment of this job. Since so much time was lost, the elevation and trigger mechanisms of the system must be urgently finished and tested with the goal of quickly discovering the suitability of using it in a tank.
The issues of other deviations in the system (materials, thermal hardening, moderator, etc) will be decided after the end of trials. At the same time, I ask you to build a separate breech wedge, piston, tail rod, and moderator according to my requirements and technologies already used in production of the L-10.
Chief of the RKKA AU, divisional commander Savchenko
Acting Military Commissar of the RKKA AU, battalion commissar Sidorov"
V. Lehn. Collection