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Does so much jump make sense?

Can anyone explain why jump distances seem to be very close between calibers and different cartridges? The 5 to 15 off jam and 30 to 40 off jam are common from 6mm br to much larger cases with tangent or hybrid bullet designs. Flame away if you feel the need or we can start a useful conversation. I understand nothing is absolute in this. Keep it general..... please.
First let me state that a hybrid has a tangent ogive in my opinion. It's either tangent or secant period. 50 years ago when I started competitive shooting I knew there was only one way I did not want to seat my bullets and that was not in the lands. After my first embarrassment with powder all over and a disabled rifle, I never did it again. So the first thing I did was find a seating depth where my bullet would get stuck in the lands and then work my way backwards until it didn't stick (Erik Cortina, this is nothing new, hee, hee!). Understand that back then we had 3 degree leads to work with and now it seems most leads hover over the 1.5 to 2 degree mark. Maybe because a bunch of lawyers got together and decided that a 1.5 degree lead will not stick a bullet or Ferris Pindall and Lou Palmisano said so. At any rate using this process and working my way off that unsafe and embarrassing situation, seems to find me shooting loads somewhere between 5 and 20 thousands off the jam, and if it fits in a repeater magazine, great. Maybe I'm just lazy and I don't want to venture past that but if it shoots in that parameter than yeah I'm good!
 
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