glass cartridge 60 retains the liquid drug during storage and shipment prior to the point that apparatus 10 is converted to its primed mode as shown best in fig2 b defined in the walls of plastic drug chamber 58 at the forward end thereof are three drug bypass conduits 64 evenly spaced around the periphery at 120 u00b0 increments while three drug bypass conduits are shown any number of conduits can be utilized however many conduits are included they should be symmetrically positioned around the periphery of plastic drug chamber 58 bypass conduits 64 include axially extending portions that extend along the length of plastic drug chamber 58 these portions are shown in section in fig2 b bypass conduits 64 also include generally radially extending portions which follow the narrowing of the plastic drug chamber fig4 and 6 all show a plastic ball valve 62 in its forward position within plastic drug chamber 58 the portions of the inward facing nozzle wall extending between bypass conduits 64 can be seen to support ball valve 62 from the sides and from the front see also fig2 5 and 6 positioned immediately to the rear of the plastic drug chamber is a plastic plug 59 the plastic plug is normally fabricated of teflon and is used to step down the diameter of glass cartridge 60 plastic plug 59 fits tightly into the forward end of glass cartridge 60 and also fits tightly into the forward end of the nozzle portion 12 the fit between plastic plug 59 and glass cartridge 60 is shown best in fig9 and the fit.