The RG-063 Baksan (РГ-063 Баксан) is a prototype Soviet submachine gun.
The RG-063 was developed by a senior researcher at TsNIITochMash, A. S. Neugodovym, who was known for his work on the APB automatic pistol. Other than this, little is known about the weapon's history.
As the main purpose of a submachine gun at the time was to have a sufficiently low rate of fire and high accuracy, Neugodovym decided to adopt an inertia-delayed blowback principle for his weapon. When fired, the breechblock and bolt move back together about 1.5mm; the speed of the bolt decreases when the gas pressure increases, but continues to cock the hammer while the breechblock is still somewhat ahead of the bolt. After the hammer is cocked, the bolt and breechblock continue to move rearward. When the hammer drops, both the breechblock and bolt move forward together, firing the round and continuing the cycle. Because the breechblock and bolt move forward and backwards slower than most submachine guns, this causes the RG-063 to have a reduced rate of fire. The weapon is select-fire.