the use of such linearly contiguous and interlocking indentations that cover essentially the entire outer surface area of the module 40 for example a pattern of hexagonal indentations that are two inches in diameter i e hexagons that can be inscribed within a two inch diameter circle may in some embodiments generate a shot pattern of 51 perforations per linear foot of the wellbore from the surface of a 4 5 inch diameter module 40 in contrast a similarly sized conventional carrier type perforating gun using conventional shaped charges will typically provide only about 18 perforations per linear foot thus this embodiment illustrates a capability to increase the perforated area by a factor of three the size and number of hexagonal indentations 54 may be varied depending upon factors such as the diameter of the module 40 relative to the size of the annular space between the perforation system 10 and the casing wall 18 the properties of the formation in which the perforation gun is being used the presence or absence of fluid in the annular space the selection of liner material and explosive and the like those skilled in the art will be able to determine optimal configurations based upon such skill and with at most routine experimentation to ensure success fig4 and 6 show additional possible configurations for the liner to enable formation of effective penetrators therefrom as illustrated therein the indentations 54 each define a cavity 60 while the perimeter of the indentations may influence the shape of the cavity 60 it is not necessarily determinative thereof thus in certain embodiments the shape of the cavity 60 may be of a generally conical or pyramidal configuration as shown in fig4 or of a generally spherical or parabolic.