With a conventional bullet it is easy to crimp them in place with either a taper or roll crimp. However with a heel bullet since the bearing surface is the same diameter as the case mouth, they cannot be crimped in the usual way. We have crimp die (not a full die set) that is designed to crimp heel bullets. The case needs to be loaded and the bullet seated and this die will apply a firm crimp to the case mouth. As the cartridge is pushed up into the die it applies pressure to a collet that then compresses onto the case mouth, crimping the bullet into place. These are set up for Bertram brass cases however, they are adjustable and can handle brass of different lengths.