Greetings Pav,
The article showing the graph is in an article called "Managing Component Variations" published March last year. In light of your recent acquisition of a .303 you might also be interested in an article called "Care and Feeding of Old Soldiers" published in May.
One thing I started doing early in my handloading is keeping records.
Attachment 158701
This is a sheet I drew up in about 1978 once I had been bitten by the handloading bug. I was loading for one rifle, a .308 which I still have, and had just started doing my first load development. I gave a copy to a young hunter starting out handloading a few years later and he is still using them. My son uses an improved version. We all keep hard copy data as this remains if your computer craps itself. Some handloaders just write the loads on the box of cartridges but this leaves no permanent record. I started with one ring binder in 1978 and now there are about eight. As well as the load records load data from the internet, some old targets and relevant notes and articles are in the ring binders. Most of my loads are stored in plastic boxes each with a slip of paper recording what they are. You will develop a system of keeping track of things that suits you, earlier would be better than later especially as the number of rifles you load for grows.
Getting back to the original question my first load development I worked up from the Speer mid load of 41.5 grains of IMR4064 behind a 180 grain Norma projectile to the max of 43.5 grains. The steps were one 1.0 grain followed by two 0.5 grain steps. The loads were fired in one session two shots per load. The impact moved up the target and the shots became closer together as the charge increased. Back home the remaining 32 cases were loaded with the top load ready for hunting. This was October 1979 a rather simpler time.
Regards Grandpamac.
