A couple of weeks ago I posted about Head space and OAL of cartridge. Quite a few of you straightened me out. When I asked about the OAL of cartridge for a particular gun and how to measure it, I received several answers. The one in particular was to load an extra length round with the bullet seated loosely then extract it slowly and measure the OAL. To be sure this was done properly I did this 6 times. Using the same bullet each time and came up with the same dimension each time, within .001" So my question is; How much of a bullet jump should I have? I realize that extra pressure is created if the bullet is touching the lands when fired, so how much relief should I give it?