Originally Posted by BCSteve
What I'm having a bit of a hard time to wrap my mind around is, if you're using a load that's been pressure tested by a manufacturer to produce "x" velocity safely with "y" amount of powder, shouldn't you be able to reproduce similar velocity? Different chamber, tighter barrel, etc may cause you adjust the powder charge to reach said velocity as your rifle may reach that pressure level sooner or later. If pressure = velocity, if you reach the manufacturer's velocity shouldn't you be within safe pressure level? What am I missing?


Steve it's just that powder lots will vary,brass will vary, barrels will vary,throats will vary,bullet jackets will vary in hardness and resistance to engraving and bearing surface,etc, etc.

All this stuff just adds up in any individual rifle (yours or mine) to produce a slightly different results.It isn't really linear and consistent all the time.Sometimes everything works spot on (you get the same result as the pressure tested load)and other times.....you don't.




The 280 Remington is overbore.

The 7 Rem Mag is over bore.