FIELD: explosion operations.;SUBSTANCE: invention concerns mining and railway construction, particularly drilling and blasting driving of horizontal and slightly sloping mines and railway tunnels. Method of cut-hole formation involves drilling of advance slightly sloping well and filling it with water. Further the cut-holes, relievers and cropper holes are drilled. Explosive charges are loaded into blast holes and well. Pinpoint blasting charge weight in the well is calculated by the well diametre, cut-hole length, physical and operational properties of cut-hole rock, overburden pressure and explosive detonation speed. Explosion of pin-point blasting charge in water generates hydroshock wave reducing shock hazard in a bump-hazardous rock bed in the zone of new face.;EFFECT: high-quality cut-hole, increased ratio of advance per blast hole during pit and tunnel driving.
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