I recently stumbled across this bit of information on how to work up a load. It came from nodakoutdoors.com, posted by “Woodser”:
Probably the best advice that can be given to someone just starting to reload for accuracy is KISS. Keep it simple. Do not go out and buy several different bullets, several cans of different powders, and a couple different primers to start with. Start with one bullet, one powder, and one primer type and work on that combo with your choice of cases until you find a load that meets your specs. Start with the published COAL, the recommended minimum powder charge and work up 1/2 grain at a time until you find a combo that produces a circular grouping, no matter what the group diameter is. Then refine that load by changing the COAL, and incrementally vary the powder charge by 0.20 grains to tighten that grouping. Change only ONE variable at at time. Changing more, or using too many different components, can prove very frustrating.
If you find a combo that appears to have tightened the group as much as it will go, then change a component. THE FIRST thing I change is the primer. Many times I have found combos that yielded 1-1.5″ groups, and changing the primer reduced that by 1/2 or more.
When working up a new load for a new rifle, I start firing 3 shot groups, and when I have found a load combo to refine, switch to 5 shots, even with a light sporting barrel.
Then in a follow-up posting Woodser adds:
I forgot to add: When changing COAL from the published, always go longer by 10-15 thou. at a step. I am assuming the reloader does not have a throat gauge, or does not wish to take the time to measure the throat by other means. I do not on either count, I just shoot until I find the optimum COAL.
Gives me more reloading, shooting and range time, don’t ya know. Since I enjoy the whole process, it is not a problem.
Those who measure the throat, and start at 5-15 thou. off the rifling, and do not vary it much during the whole load work-up cycle, may miss the sweet spot OAL for his rifle. Said sweet spot might well be 10 thou. off the lands, but it might also be 50-80.
I wish I had that advice when I started reloading. Granted, the only reason I can view that as really good advice is because of hindsight. But it’s something I’m going to take to heart as I go along.
The key would be to start with the known. So you have a good book, like the Speer #14 manual, or other solid sources of complete reloading data. Pick components (bullet, primer, powder, cases) based upon what’s established in the book. Of course these days it’s kinda hard to get exactly what you want due to supply and demand issues, but still pick something that’s in the book and as close as you can get… or at least, just pick one thing and stick with it. Work with that one thing. Vary powder and seek accuracy, working powder charges until you find what works best in your rifle. Then once you’ve exhausted powder (i.e. changing that one component), move to another component and see what happens.
And keep good records of everything.