A spiral magnetic-flux compression generator with simultaneous axial initiation of an explosive charge is treated. An external solenoid is used to develop the initial field in the generator. A theoretical model of this generator operating into inductive storage and to break point of the current circuit is described. Experimental results are given obtained in testing a generator with an inside diameter of the spiral of 115 mm and a working volume length of 330 mm. A 100-GW current pulse is obtained at a break point of electrically exploding copper conductors. The experimental results are compared with the results of numerical simulation of the generator operation.