less than the cartridge selected so that the cartridge may be slid easily and smoothly into its seated position shown on fig5 and 6 and is of sufficient length so that the cartridge will remain perpendicular to the central portion 11 of the body and parallel to the other cartridges for the 38 special loader illustrated the diameter of guide portion 28 is 0 372 inches compared to a cartridge shell diameter of 0 374 inches and the axial length of the guide portion is 0 227 inches the entire thickness of the body 10 or height of sidewall 16 is 0 275 inches although body thickness in the range of about 0 240 to 0 300 will operate each of the apertures and with continued reference to the example of aperture 21 in fig5 and 6 has a rim guiding and release portion 29 that is a frusto conical surface connecting cylindrical guide portion 28 and rear wall 13 the frusto conical surface 29 in fig6 has a 45 degree taper angle which is preferable but the taper may vary to 40 degrees with respect to the centerline 30 of the aperture 21 and operate satisfactorily an important characteristic of the configuration of the surface portion 29 is that it has an outer diameter greater than the outer diameter of cartridge rim 32 this enables the lower or forward edge of the cartridge rim 32 to seat below rear wall 13 so that during.