Use more than one data source (reloading manual from a manufacturer, not online recipes)
I have three, Speer (my favorite), Lyman and Lee. I choose Speer first because the data is the most objective. Lyman is overlly conservative to the point that it affects the usefulness of their data. Lee's data is affected by his persoanl preferences and his past dealings with others in the industry.
My load for 30-30 is 29gr IMR 3031 with Remington Flat Point 150s. It aint gonna set no record but it does the job and thats all I ever wanted. The 30-30s I have all seem to like it well enough. Start with a lesser loading, load twenty shells and bench them. Go up as you wish and stop before you get outside safe limits. Decide which if any loads had better accuracy. This is based on the 3031, if yoy want to try Reloader 7 consult the books, Ive never used it.