Process for the manufacture of an elastomer composition having a self-sealing property which is based on at least (phr meaning parts by weight per 100 parts of solid elastomer): a blend of at least two solid elastomers, a polybutadiene or butadiene copolymer elastomer, referred to as “elastomer A”, and a natural rubber or synthetic polyisoprene elastomer, referred to as “elastomer B”, the elastomer A:elastomer B ratio by weight being within a range from 10:90 to 90:10; between 30 and 90 phr of a hydrocarbon resin; from 0 to less than 30 phr of filler, in which, during a first stage or stage (a), a masterbatch comprising at least the elastomers A and B and between 30 and 90 phr of a hydrocarbon resin is prepared by mixing these various components in a mixer at a “hot compounding” temperature or up to a “hot compounding” temperature which is greater than the softening temperature of the hydrocarbon resin.