There is a very interesting article in the October issue of Shooting Times magazine. The article by Lane Pearce is titled “Tracking Pressure as Powder Charge Increases.” One of the accompanying charts is hosed-up (the numbers in the left hand column are reversed) but the article and charts are very interesting and of considerable use to the handloader and wildcatter.
The article demonstrates how graphing your handloads can help you identify your practical maximum load for a given combination of load components in a specific firearm. We have graphed handloads for many years. Prior to having a chronograph or electronic computer we compared powder charges, bullet drop and pressure ring expansion using graph paper and colored pencils, a frustrating exercise! With chronograph data, graphs can be quite useful. For those who don’t desire to fiddle with Excel or Lotus graphs Greg Mushials RCBS Load has built in graphs that are easy to use.
When working with wildcat cartridges where there is no reliable reloading data graphs are especially useful in establishing reasonable stop points that ensure a margin of safety.
The article is well written, easy to understand and worth a little study.