RDub
Member
Hmm..
Ok lets yak about this..
I have a chronograph, an Oehler Mod 33. I've had it since 1980.
When I worked up this load, 180 Nos Par ahead of 72.0grs IMR4831, I shot 3-shot strings in 0.5grn increments. The velocity, ES(spread) and Sd Standard Deviation remained pretty uniform all the way up to 72.0grs where I stopped.
That velocity averaged 2970fps.
Sometimes,.. when you working up the strings and you get into high pressure, and this is known by the pressure signs we are familiar with and what the books say.. you will see velocities stop increasing, or going the other way, getting slower. Of coarse this means you are way past where you should be!
In this instance I didn't see any of these signs.
Now, if this load, 72.0grs, is generating pressures in the 70,000psi range, why is the velocity only 2970fps?? And the velocities of the strings working up to that were fairly uniform as they increased.
I should be seeing much higher velocities with that much pressure.
What do you think?
Ok lets yak about this..
I have a chronograph, an Oehler Mod 33. I've had it since 1980.
When I worked up this load, 180 Nos Par ahead of 72.0grs IMR4831, I shot 3-shot strings in 0.5grn increments. The velocity, ES(spread) and Sd Standard Deviation remained pretty uniform all the way up to 72.0grs where I stopped.
That velocity averaged 2970fps.
Sometimes,.. when you working up the strings and you get into high pressure, and this is known by the pressure signs we are familiar with and what the books say.. you will see velocities stop increasing, or going the other way, getting slower. Of coarse this means you are way past where you should be!
In this instance I didn't see any of these signs.
Now, if this load, 72.0grs, is generating pressures in the 70,000psi range, why is the velocity only 2970fps?? And the velocities of the strings working up to that were fairly uniform as they increased.
I should be seeing much higher velocities with that much pressure.
What do you think?