I use the PPM only, it is a volume device so it isn't supposed to give you a singular weight.
So here is the deal for Extruded powders only. They have their burning rates controlled by geometry, meaning volume. An extruded powder with a higher bulk density (more nitro) will have a correspondingly slower burning rate; the inverse of this is also true. Fundamentally burning rates don't change if you cut a kernel, so don't let that worn out argument bother you. If you load only by weight, you ignore this design function. And if you have the newest Norma manual, there is some wonderful test data on how much burning rates shift (loaded ammo, or sealed powder bottles) from changing moisture content. Well if you are only loading by weight, you are potentially aggrevating the burning rate issue, with a BD shift due to moisture.
So personally, I do a VMD for my bottles of powder, then begin loading. Other than
Testing my bottles VMD, I haven't weighed a powder charge in close to a decade; this includes the loads I use to a mile in a few rifles.
Is this the only way to do it? Of course not, but it's what I do. Either my marksmanship is world class and overcome a stupid loading technique, that no one knows about. OR a volume loading technique is at least as good as any weight system, and I'm a pretty decent shot also.
Choose whichever seems more reasonable.
Last edited by Darkker; 02/12/17.
