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Old 01-28-2008, 12:15 AM
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ar15barrels ar15barrels is offline
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Originally Posted by Nom de Guerre View Post
You wrote, "I'm shooting 155 SMK's at 2875fps and I still have some margin to warm up the load some more."

How do you know how much further you can push your load? Is the pressure generated by the load combination (bullet, powder type, powder charge, etc.) the main determining factor of the safety margin?

Are you using a ballistic program to help determine how fast you can push the 155 Scenar before getting into the danger zone?
A combination of Quickload, chronographing, shooting "pressure series" in small steps to check for signs and accuracy and just past experience in all these things.

It happens that Quickload predicts velocities within about 15fps of what my chrono reads so it has to be DAMN close on pressure too.
Comparing loads that show pressure signs like flat primers, ejector swipes and hard bolt lift also shows the loads to be over-pressure in Quickload.
These experiences have lead me to trust quickload a lot because I know how to manipulate it to get good data out of it that happens to be matching actual measured field conditions.
Randall Rausch

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