In trying to find bullet jam, I de-primed several fired cartridges and put bullets in long. Each one measures very different. In re-doing this with the same cartridges, I noticed that each cartridge measured the same each time, but they were all different in CBTO measurement. So then I measured case lengths. They are all different. But how should this affect the bullet jam measurement? After all, we are still measuring from the base to the ogive. So the case length should not matter . . . . . should it? And how critical is case length to accuracy? How much can they vary? Thanks for the help.