tube above the barrel. However, the new Kalashnikov design lost out to a Simonov design. In 1946, a new design competition was initiated to develop a new rifle. Kalashnikov submitted a gas-operated rifle with a short-stroke gas piston above the barrel, a breechblock mechanism similar to his 1944 carbine, and a curved 30-round magazine. Kalashnikov's rifles, the AK-1 (with a milled receiver) and AK-2 (with a stamped receiver), proved to be reliable weapons and were accepted to a second round of competition along with other designs. These prototypes (also known as the AK-46) had a rotary bolt, a two-part receiver with separate trigger unit housing, dual controls (separate safety and fire selector switches) and a non-reciprocating charging handle located on the left side of the weapon. This design had many similarities to the StG 44. In late 1946, as the rifles were being tested, one of Kalashnikov's assistants, Aleksandr Zaitsev, suggested a major redesign to improve reliability. At first, Kalashnikov was reluctant, given that their rifle had already fared better than its competitors. Eventually, however, Zaitsev managed to persuade Kalashnikov. In November 1947, the new prototypes (AK-47s) were completed. The rifle used a long-stroke gas piston above the barrel. The upper and lower receivers were combined into a single receiver. The selector and safety were combined into a single control lever/dust cover on the right side of the rifle. And, the bolt-handle was simply attached to the bolt-carrier. This simplified the design and production of the rifle. The first army trial series began in early 1948. The new rifle proved to be reliable under a wide range of conditions and possessed convenient handling characteristics. In 1949, it was adopted by the Soviet Army as "7.62 mm Kalashnikov rifle (AK)". Further development There were many difficulties during the initial phase of production. The first production models had stamped sheet metal receivers with a milled trunnion and butt stock insert, and a stamped body. Difficulties were encountered in welding the guide and ejector rails, causing high rejection rates. Instead of halting production, a heavy machined receiver was substituted for the sheet metal receiver. Even though production of these milled rifles started in 1951, they were officially referred to as AK-49, based on the date their development started, but they are widely known in the collectors' and current commercial market as "Type 2 AK-47". This was a more costly process, but the use