QL estimates your pressure, velocity, and even barrel time. This has nothing to do with how the load will perform accuracy-wise.
All the qualifiers you mentioned to follow(QL calibrations) are not predictions, but DISCOVERY.
You have to discover to calibrate.
What folks are doing is finding best loads(however they do) -and then backwards analyzing to make a desired correlation with that discovered load and OBT.
Well, it doesn't matter what correlation you make to OBT once you already found your best load through other means!
It's not prediction of best load.
It's not a shortcut.
You are taking my use of "perform" out of context Mike. I was meaning what QL lists, i.e., Loading ratio, case fill, charge weight, pressure, propellant burnt, barrel time, etc. I wasn't talking about accuracy until I said:
"If you take the time to enter your guns profile, measure your components (bullets weight, length, diameter, case length and H2o capacity) and enter them into QL, adjust the weighting factor correctly for the cartridge, adjust the burn rate to match chronographed velocities, it can estimate what will be a performing charge and what would be a waste when coupled with Chris longs node tables."
They key is the last part-
when coupled with Chris Longs' node table. Although seems like pressure, velocity, and barrel-time surely correlate between two accurate loads in my 25/06:
100gr BTIP: +00.0 91 XX.XX 3125 2169 43642 12624 97.9 1.226 (IMR 4831)
110gr Accubond: +00.0 101 XX.XX 3078 2314 49381 12797 99.8 1.227 (RE-25)
You are right, the qualifiers I mentioned are empirical "discoveries" found on purpose. However, I prefer to think of them as measurements though. Wondering where you got the idea that I said they [the qualifiers] were "predictions".
And, well... Agree to disagree on your last point. I have several loads that were estimated in QL and the OBT table for my rifles lengths before I stepped foot onto the range. -Mind you, I did my due diligent homework and verified that my charge needed for the node was within published data and I had velocity measurements of the powder's lots. I had previously shot other load combinations at higher pressures (10-15K higher) in the rifles so I was confident that I was seeing safe combinations in QL that matched a node in CL's table. My result- fastest load development I have ever completed. Three in the same hole? I'd accept that for a hunting rifle. 25/06, 100gr BTIP. Performs just as well as my 110gr Accubond load, each are leaving the barrel at the same node and have roughly the same velocity.
I could post a few more of my loads and several friends' loads that I assisted with but I'm not going to hijack this thread anymore. I'm convinced that my method has proven itself useful, safe (I wont be charging up loads near to or past published max's if I see I wont be reaching a node), frugal and results in pretty decent accuracy.
Your results may vary.