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Old 05-08-2007, 01:53 PM
scootertrash scootertrash is offline
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Join Date: Nov 2006
Location: Lake George, Colorado
Posts: 257
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Dan,

I typically start with the burn rate adjustment, usually +/- 5% gets me close to matching actual velocity.

I shoot both a known low safe load, and a load a with a heavier charge. After adjusting the burn rate as closely as I can, I then adjust the "weighing factor" in QL until the velocities at both the low and high charge will match very closely to the actual at both ends. For the .20 VT, I have found a weighing factor of .36 works well.

Also I have found if you are loading into the lands, QL's recommended shot start pressure is high. I don't load my .20's into the lands, as I shoot a couple thousand rounds thru each in the summer, and it makes it easier to chase the lands when shooting pdog quantities of ammo. With my 6 PPC's though, somewhere between 5000-6000 on the shot start works well for me and several others on the 6BR forums.

The best way I have found to determine this, is first adjust your burn rate and weighing factor without touching the lands. Now that your parameters are known, chrono the load touching the lands, and then adjust the shot start pressure up until the programs velocity matches your chrono speed.

And thanks for your explanation on the "clicking" question the other poster inquired about. And I agree about the Cooper's extraction system.

Mike