120 class powders

[SCJim]

Nubi,


As I said, I am basing my 'stance' on common sense chemistry. Specifically the principle that more powder = greater, or even equal velocity - [U]but never less velocity[/U].

One old timer told me that if you see a decrease that indicated overpressure and the velocity decrease was due to case stretching and th eprimer leaking and or backing out. That's just hearsay of course. I have never seen more powder equal less velocity but never have I seen a linear correlation either. I have been basing my load development for several years now on looking for flat spots in th epowder/velocity curve and loading to the middle of those to give myself some leeway on temperature and charge measurement accuracy. I have no idea why adding .3 gns of powder at one stage can give a 50 FPS gain velocity and the next .3 increase will only give a 5 FPS increase. But those 5FPS nodes give me the best load performance