Assessing the modern constructions of barrel weapon systems, one can rightly claim that they have achieved a high level of development both in terms of construction and technology. This is confirmed by the fact that it is quite rare for new solutions to appear in this area, with regard to their operational concept. It is also confirmed by many existing classifications of barrel weapons, taking into account the present constructional solutions used. In the present paper, the author described a new type of mechanism, which as for its operational concept, consists in separating the breech parts, being used in the weapons class of a short recoil barrel. The principle of its operation and constructional solution have also been presented, along with the mechanism that has been used so far, which enables us to show the basic operational difference between the two. In order to assess the value of the proposed mechanism, an analysis has also been made of parameters characterizing its operation, contrasted with the parameters of the mechanism used so far. This comparison has been drawn, taking into account the same object of reference, i.e. the NS-23 gun. In the summary, conclusions have been presented assessing the merits of the new solution.