I have been reloading a long time - so long I am probably in the 'Top Twenty' of the veteran reloaders on this forum. Anyway for the most part I have taken it seriously, spent time studying loads powders, techniques etc. and for the most part have a fairly advanced understanding of how everything works, the relationship of powders to calibers, case capacity and pressure anyway I have pretty good working knowledge of the science of reloading. Recently however I have been looking into developing some light loads with lead bullets for 30-30 not only for my self but for a friend of mine who just bought his son a used Marlin and would like to be able for him get comfortable with it before moving up to hunting velocity rounds (which I will also be making). Anyway I cannot find much in the way of data for lead bullets other than using 7-8 grains of Unique with 130 - 150 grain lead bullets. I was wondering why other typical pistol data could not be used, for example - if I can load 16 grains of WW 296 with a 158 grain bullet (a 'standard' .357 load) and shoot it out of my Winchester Trapper, then why couldn't I use the same data in a 30-30 round with say a 150 grain bullet? I would be equating the nearly the same load as the .357 but 296 is not recommended in any rifle. Is it an issue with a bottleneck rifle case that changes things? Just wondering as this is a new arena with me and I want to approach it correctly.