OK, let's start specifically with Enfield-pattern bullets. What makes one specimen truly a "different" bullet?
DIAMETER: Assuming all measured diameters are averages, how much difference in diameter make a bullet "different"? I'll suggest 0.1" or more. Responses???
LENGTH: This is usually more uniform than diameter measurements. But same question, how much longer or shorter makes it a different bullet? Again I'll suggest 0.1" or more. What say you all???
CAVITY: This one sounds easy. And obvious differences (plug vs. cone vs. stampings) are simple to decern, but what about variations in (for example) a cone cavity? I suppose depth of cavity also needs to be considered.
SKIRT: There are differences in the thickness of the skirt around the base. What other differences do you encounter? Do you consider what some call the "false insert" a real difference?
NOSE/PROFILE: If nose cast, the sprue is hand trimmed. Obviously a worker with a "heavy hand" will cause a different shaped bullet than another worker will ... even though the identical bullet pattern was begun with. Should this really be considered a variation of that type of bullet?
If machine pressed, how do we address the "rings" often left in various locations on the bullet from pushing rods ... if all else about the round is the same?
Let us hear your thoughts on this. If each of you are at a relic show, what is it about an Enfield bullet that makes you consider buying it? How is it different than all the others in your collection.