Not sure about this.

n/a

I just read about working up loads for a 404 big bore. The author stated that he could get 75 - 125 higher fps with one powder over another with the same chamber pressur. He was using the strain gages. This does not seem correct.

MIKE WISKEY

most rifle powders have the same 'energy' content per grain (weight), there are however many different 'burn' rates. a 'faster' powder will have a shorter pressure 'curve' and a shorter bearing time on the bullet than a 'slower' powder.

Hawk Carse

It can happen. It just means his first powder was not a very good choice for the caliber and the second was more progressive burning and probably a bit slower.

charliemeyer007

I think the strain gauge system picks up pressure spikes the copper crusher system never sees.