One aspect of the invention concerns a method of charging an upwardly oriented hole with a pumpable material, typically a pumpable explosive material such as an ANE. In the method of the invention a laterally expandable retainer is provided. This is of smaller length than the hole and has an inlet at a lower end thereof and an outlet at an upper end thereof. In an unexpanded state the retainer has a smaller lateral dimension than the hole. The retainer is inserted upwardly into the hole in an unexpanded state, whereafter material with which the hole is to be charged is pumped upwardly into the retainer through the inlet such that the retainer fills up and expands laterally into engagement with a wall of the hole. Excess pumped material is allowed to upwardly out of the retainer into the hole through the outlet. After the retainer has been filled with material and the hole above the retainer has been at least partially filled with any excess material, the pumping operation is stopped and the inlet is closed. The material is then retained in the hole by engagement of the filled and expanded retainer with the wall of the hole. Another aspect of the invention concerns the apparatus used in the method.