The paper presents experimental and numerical results of the investigation of fragmentation process of copper rings expanded with maximum radial velocity close to 170 m/s. The experiments were performed on Cu-ETP rings of average diameter of 32 mm and cross-section of 1 x 1 mm. The authors particularly focus on the statistical concept of the ring fragmentation process. In connection with the above, the number of fragments, their size and distribution were determined on the basis of multiple experimental ring tests. It was established that for selected loading condition, the copper ring fracture appeared when the strain reached the average values of 0.35 and the average number and length of fragments were about 11 and 13 mm, respectively. Moreover, the numerical prediction of the fragment size distribution was carried out using the Mott fragmentation model.