Quote Originally Posted by EddyQ View Post
Because it would seem that with bullet of greater weight you would want a greater charge. Or for a lighter bullet you would want a lighter charge.
A firearm is a pressure vessel and must be kept within pressure limits to operate safely. It takes gas pressure (powder burning inside a small area ) to push the bullet out of the barrel during the pressure curve.

As a heavier Bullet takes more pressure to overcome its mass and surface area, using a powder charge that pushes a lighter Bullet out of the barrel before the internal pressure reaches the level that exceeds the structural integrity of the firearm can push those pressures beyond that point.

A powder charge burns in an incredibly short period of time in an very small space. The faster the powder burn rate, the faster the maximum pressure that powder charge achieves its maximum pressure. Couple that with a projectile that cannot leave the barrel before maximum safe pressure is surpassed in a given firearm and bad stuff happens.

Always cross reference a given load data between multiple sources correlation to the type of firearm used, AND EXCEED IT AT YOUR OWN AND OTHERS RISK.