The objective of this work is to evaluate technically and economically the drilling and blasting of 20 feet fronts, through the tests carried out in Cía. Minera Condestable, which allowed me to change the drilling system from 14 to 20 feet, which resulted in greater progress in emergency work.The method of exploitation of long holes in breaches and seams, makes a requirement of several meters of preparation work for long drilling equipment and development as galleries, sublevels etc, to reach the ore. In the mine there are 2 shifts (day and night) and only blasting is done at 6:30 a.m. and 6:30 p.m., therefore, only two shots of 14 feet can be made in the same work, now if the work is urgent the shots would be implemented with the 20 feet giving more progress at a higher cost as we will see in the results obtained.