The small arms generally capture a significant range of infantry weapons that an individual soldier can carry and operate. Excessive use with inadequate maintenance of these weapons gradually forms abnormalities like corrosion, crack, bulge, and particle deposition on their inner surface. Such abnormalities inspection has been conventionally manual (with open-eyes), tedious, inefficient requiring much effort and time, and susceptible to incorrect detection. Therefore, this paper presents a new software-based inspection system with automatic detection and estimation of the surface abnormality as a timely requirement. The state of abnormalities is determined and characterized for the small arms made of steel that eventually result in different faults and reduce the weapons’ efficiency. A software-based system is designed with a high definition, small-aperture, and low-powered camera to acquire, process, and analyze the inner-surface images in real-time. The surface abnormalities are then determined and estimated according to the detected features of the abnormalities. The proposed system would offer an effortless early-detection and more accurate estimation of the inner-surface abnormalities to ensure appropriate diagnosis and longer lifecycle of the small arms.