Aiming at the problem involved in canal wearing when bomb is loaded and aligning striker to primer, a technology is introduced for automatic detection of the total run-out error of bomb tail bourrelet. It is composed of the automatic lifting mechanism, the driving mechanism, the holddown mechanism and the measuring mechanism. The automatic-detecting equipment is directly mounted to bomb transmission product-line frame so as to checkout the total run-out error of bomb tail bourrelet at detecting workspot on bomb transmission product-line instead of bomb off-line detection. All operations such as lifting, locating in axial or radial direction, rotating and detecting can be completed automatically. Only the value of total run-out error is fetched manully via dial indicator. It shows that the technology can improve the safety and automation level in bomb production, lighten the labour intensity of operating personnel and uprate labour productivity.