Quickload and Double Based Powder

[BCBRAD]

I have been using Quickload for a while now and find that as long as the inputs are accurate the predicted velocity is very close to actual chronograph ed velocities.
So here is a problem , I am loading for a 9.3x66 Sako, VV N-550 powder and a 250gr AccuBond. QL states 66.16grs of N-550 will yield 2615 fps. I get ~2408fps . I also chronograph ed other loads on different rifles at the same time.

Does QL have a problem with Double Based Powders? or is there something else?

 

[Milo 2.0]

I think the more you use QL, the more these discrepancies will pop up. I thought QL was the holy grail at first myself.

The guy who developed QL knew what these powders were, so I say no to your final question.

 

[SmokinJoe]

Seems any double base powder gives considerable variation depending on temperature. I have QL on my laptop in my shop, but can't remember whether temperature is addressed in the setup info, but think it probably is. Could that be the problem with the mismatch?