elongated substantially solid steel cylinder of sufficient strength and solidity to withstand the pressures generated by the firing of gun assemblies 14 such as the gun body of the commercially available dresser atlas e gun bullet perforator as indicated in fig1 between apparatus 10 and cablehead assembly 17 is a sub 18 which may include a firing head assembly or some other related device these subs are well known in the art and are not part of the present invention referring now to fig2 there is illustrated a cross sectional view taken along the lines 2 2 of a typical bullet perforating gun assembly embodying the present invention the actual construction of the gun assembly may vary depending upon the type of use and downhole conditions encountered for example different bullets are used for perforating different formations gun barrel length may vary for different propellants and propellant composition and placement may vary upon the downhole temperature none of these variants however are restrictive of the invention disclosed herein gun body 12 is provided with apeture 15 comprising laterally extending coaxial bores 20 and 22 the smaller diameter bore 22 extends innermost and forms the propellant chamber positioned within bore 22 is a cartridge tube 24 containing a quantity of propellant 26 as mentioned before the composition of propellant 26 is dependent upon the type of use and downhole conditions encountered and is not restrictive of the invention herein described an igniter 28 extends into the.