User blog comment:CustardBird/The EMERGENCY Weekly Custard - August 5th, 2016/@comment-25169725-20160805134233

The SVT-38 saw its combat debut in the 1939–1940 Winter War with Finland. The initial reaction of the troops to this new rifle was negative. Among the issues were that the rifle was too long and cumbersome, difficult to maintain, and the magazine had a tendency to fall out of the rifle. Production of the SVT-38 was terminated in April 1940 after some 150,000 examples were manufactured. Subsequently, an improved design, designated the SVT-40, entered production. It was a more refined, lighter design incorporating a modified, folding, magazine release. The handguard was now of one-piece construction and the cleaning rod housed under the barrel. Other changes were made in an effort to simplify manufacture. Production of this improved rifle began in July 1940 at Tula, and later at factories in Izhevsk and Podolsk. Production of the Mosin–Nagant M1891/30 bolt-action rifle continued, remaining the standard-issue rifle to Red Army troops, with the SVT-40 more often issued to non-commissioned officers and elite units like the Naval Infantry. Since these factories already had experience manufacturing the SVT-38, production geared up quickly and an estimated 70,000 SVT-40s were produced in 1940.