Process for the manufacture of a long glass fibre reinforced polypropylene composition containing from 10 - 70 wt.% of glass fibres based on the weight of the composition, the process comprising the steps of: a) providing at least one continuous glass multifibre strand, b) applying a sheath of a polypropylene composition around said continuous glass multifibre strand so as to form a sheathed continuous glass multifibre strand, c) cooling the sheathed continuous glass multifibre strand to a cutting temperature, d) cutting the sheathed continuous glass multifibre strand into pellets at said cutting temperature using a rotary cutting tool; said rotary cutting tool comprising a rotary cutting wheel comprising a cylindrical supporting spindle and several cutting blades positioned on the outer surface of the spindle, and a cutting guide, being a cot wheel comprising a cylindrical roll having an even surface which is covered with a layer of an elastomeric material, wherein, in use, the rotary cutting wheel and the cutting guide co-operate such that the continuous glass multifibre strand is cut into pellets wherein said cutting temperature satisfies the following equations I, II and III T _ max = − 0.625 × GF + 112.5 T _ min = 10 T _ min ≤ T _ cut ≤ T _ max wherein T_cut is the cutting temperature T_max is the maximum cutting temperature [°C] T_min is the minimum cutting temperature [°C] GF is the amount of glass fibres based on the weight of the composition [wt.%], the process further comprising a step of applying from 0.5 to 20 wt.% based on the weight of the composition of an impregnating agent to said at least one continuous glass multifibre strand before step b). a) providing at least one continuous glass multifibre strand, b) applying a sheath of a polypropylene composition around said continuous glass multifibre strand so as to form a sheathed continuous glass multifibre strand, c) cooling the sheathed continuous glass multifibre strand to a cutting temperature, d) cutting the sheathed continuous glass multifibre strand into pellets at said cutting temperature using a rotary cutting tool; said rotary cutting tool comprising a rotary cutting wheel comprising a cylindrical supporting spindle and several cutting blades positioned on the outer surface of the spindle, and a cutting guide, being a cot wheel comprising a cylindrical roll having an even surface which is covered with a layer of an elastomeric material, wherein, in use, the rotary cutting wheel and the cutting guide co-operate such that the continuous glass multifibre strand is cut into pellets wherein said cutting temperature satisfies the following equations I, II and III T _ max = − 0.625 × GF + 112.5 T _ min = 10 T _ min ≤ T _ cut ≤ T _ max wherein T_cut is the cutting temperature T_max is the maximum cutting temperature [°C] T_min is the minimum cutting temperature [°C] GF is the amount of glass fibres based on the weight of the composition [wt.%], the process further comprising a step of applying from 0.5 to 20 wt.% based on the weight of the composition of an impregnating agent to said at least one continuous glass multifibre strand before step b). T_cut is the cutting temperature T_max is the maximum cutting temperature [°C] T_min is the minimum cutting temperature [°C] GF is the amount of glass fibres based on the weight of the composition [wt.%], the process further comprising a step of applying from 0.5 to 20 wt.% based on the weight of the composition of an impregnating agent to said at least one continuous glass multifibre strand before step b).