Re: lower preassure better?
Yes, the simple answer is you ARE missing something. The companies that put out powder and bullets and reloading manuals all have adopted a "keep it safe" attitude for liability reasons... and I don't blame them. This has moved into the way that they post pressures in the loading information. If the average of 20 shots with 50 grains of powder A is 2500 fps and the pressure averages 50,000cup all should be well in our uninformed mindset. But the companies have to have it safe. An example: the same 20 shots with powder A has pressure variances that run from 44,500 to 59, 500cup with the majority being under 50,000 but several big spikes in pressure run the average up. The companies will NOT report this as 50,000cup average pressure!!! What if someone uses this data and has a pressure spike with disastrous results??? Liability issues big time. Instead they report the spike pressure!!! and they modify their loads downward accordingly. It is a well know fact that some powders tend to have bigger pressure variances in certain cartridges. You are safer and will get better results from your handloading looking for powder and loads that produce the HIGHEST pressures rated in the manual. They will still be safe!, but they won't have as much pressure variances as loads with low pressures that are reported. In other words, they have fewer spikes, and that means more "repeatability" for lack of a better term.
I recommend the Hodgdon Powder Manual No. 27 for its review on pressures. A quote from that source..."If the pressure for a given load combination is listed at 49,400 CUP, then that combination of components tends to have a slightly lower pressure spread than a load that is listed at an average of 48,000CUP."
Hope this is clearer to you, the reader than it was to me when I first read it. Also, I hope this helps out.