I’m preparing for my 1st reloading project. I purchased Berry’s 38/357 158GR RN bullets. I will be reloading approx. 300 rounds of .38 spl. I inherited quite a bit of old powder from the 1990's that I know was stored in an appropriate environment. I have read that powder stored well lasts for very long time. I would like to use the powder I have rather than purchase new powder. I have a 1lb can of 231 that’s never been opened and a half full open can of 231. I read that 231 is a popular powder for .38 spl. I’ve been looking at load formulas specific to the 231 powder from the sources I inherited. I’m struggling to understand the load data from the various sources. I interpret it to have a wide variation from source to source which seems odd but again, I am just starting out. I understand from Berry’s Bullets site I can use any formula as long as it is for the 158gr bullet and it does not exceed the max velocity for the bullet. In this instance, 1250 fps. Modern Reloading Lee Richardson 2nd Ed. = (lead bullet) start 3.1gr / 782fps. *Not to exceed 3.7gr Sierra handgun Reloading Manual 50th Anniversary = (JHC & JSP) 4.9gr / 850fps Speer Reloading Rifle & Pistol Manual #12 = (L-SWC, L-HP, L-RN) 4.0gr / 792fps & 4.4gr 878fps If Lee manual states not to exceed 3.7gr how can 4.0gr & even 4.9gr stated in Sierra and Speer respectively be safe?