09-13-2013, 04:08 PM
XCountryRider,
Significantly higher than normal velocities ONLY can occur under 3 circumstances:
1) Pressure is higher than expected.
2) Barrel length is longer than expected.
3) Chronograph readings are incorrect.
There are no barrels that can create higher velocities than other barrels created in the same manner, at least those of equal length and within acceptable manufacturing tolerance. I have two Satern 5R barrels, my readings are within normal variation, as are the VAST majority of peoples readings using Satern and Liberty barrels, as many have pointed out.
Therefore, one of the 3 variables above must be at work. Since 2 and 3 are not dangerous, everyone is concerned about 1.
We have members here who can model that velocity and work back, using computer programs, to give us an idea of what kind of pressure those programs will predict. I've asked one of them to do so.
There are chambering and manufacturing variables that can affect velocity, but achieving 100 FPS of extra velocity on the upper end of a load takes a lot! Consider that a 6.5 Creedmoor shoots a 123 at only about 2700 FPS using 6-10 more grains of powder and creating 4000-10000 more pounds of pressure, depending on the powder.
We don't want any faces blown up. The guys who wrote the Grendel reloading book spent A LOT of time talking to Bill Alexander, Hodgdon, Western Powders, etc. making sure the data was both good and safe. When they see velocities that don't make sense, they get nervous, as do I.
We like our members, we don't want anyone hurt!
Significantly higher than normal velocities ONLY can occur under 3 circumstances:
1) Pressure is higher than expected.
2) Barrel length is longer than expected.
3) Chronograph readings are incorrect.
There are no barrels that can create higher velocities than other barrels created in the same manner, at least those of equal length and within acceptable manufacturing tolerance. I have two Satern 5R barrels, my readings are within normal variation, as are the VAST majority of peoples readings using Satern and Liberty barrels, as many have pointed out.
Therefore, one of the 3 variables above must be at work. Since 2 and 3 are not dangerous, everyone is concerned about 1.
We have members here who can model that velocity and work back, using computer programs, to give us an idea of what kind of pressure those programs will predict. I've asked one of them to do so.
There are chambering and manufacturing variables that can affect velocity, but achieving 100 FPS of extra velocity on the upper end of a load takes a lot! Consider that a 6.5 Creedmoor shoots a 123 at only about 2700 FPS using 6-10 more grains of powder and creating 4000-10000 more pounds of pressure, depending on the powder.
We don't want any faces blown up. The guys who wrote the Grendel reloading book spent A LOT of time talking to Bill Alexander, Hodgdon, Western Powders, etc. making sure the data was both good and safe. When they see velocities that don't make sense, they get nervous, as do I.
We like our members, we don't want anyone hurt!
You seek escape from pain. We seek the achievement of happiness. You exist for the sake of avoiding punishment. We exist for the sake of earning rewards. Threats will not make us function; fear is not our incentive. It is not death that we wish to avoid, but life that we wish to live. - John Galt