Interesting info on load testing and development

[Hubcap]

Not sure what this guys credentials are, but seems to be quite knowlegable.

http://kwk.us/ibsw.html

http://kwk.us/chronographs.html

[EdMc]

The second article gives some 'interesting' results of the effects of just changing primers. Small velocity gain with a not so small gain in pressure.  Knowing the powder used in that testing would be of help as I'd think the relationships would vary with the burn rate of the powder used.

[Taterhead]

I think this puts numbers behind what we all know to be true. Changing even one component can have material effects on pressures.

I saw this firsthand. I traded rifles with my father in law. He used my data for a load developed in the rifle - except he changed brass and primers. He sent the rifle back plus the brass he had fired. I don't know why he did not realize that there were definite indications of excessive pressure. I asked him about it and he said he did not notice, and that he had just loaded the same "recipe" that I did. Truly it was not the same "recipe" because brass has different interior dimensions and thus internal volume. Primers obviously have different sparks too.

[pasky2112]

Very interesting.  I would have like to have read this last week.  Even if some of the data is 'missing', the data he detailed and the conclusions are very telling.  The measure of unpredictability is pretty eye opening. 
The bleeding edge can be indeed...

[REDLINE]

Great info.  Thanks for posting it.