Having reloaded on and been a dealer for P/W for over 35 years, I have to disagree with the above "experience" on the P/W bushing light loads... unless you feel that maybe .1-.2 grains is an issue.
I find the NO manufacturer's recommended loads throw EXACTLY what they list. They do build in a small amount of liability assurance.
What REALLY makes a difference are:<BR>
1. Different powder lots by the manufacturer<BR>
3. Humidity and Barometric Pressure<BR>
4. How YOU operate the machine (fast/slow/smooth/jerky)
Take the advice on what JOHNNY's comment and do BOTH the research and weigh YOUR loads.