What impact does load density have on load accuracy? Is there a place to be for optimum accuracy,for instance 90% load density for optimum accuracy? :?
I have also asked this question on other occaisions. The most common answer that I get from experienced reloaders is that the closer you can get to full case capacity the more consistent your cartridges will be. But often, in many loads, even the heaviest load is not anywhere close to full case capacity. So . . . it is hard to really know.
The concept behind higher density is uniformity of burn, caused by the small, consistent powder surface exposed to the primer flash. Low density loads might sometimes have powder up against the flash hole, but other times exposing a long, horizontal surface to the flash. The latter will burn faster than the former, causing variation in pressure peaks among shots.