Tenmilephenom
I'm using reg win 209s
That is probably a good idea...
If you had a chrono you could clock you load then start backing down in 10 grain increments and if the velocity dropped you would know you are getting the most out of your powder but if stays the same you are getting a good burn.
Another way as some of the old timers tell me you could shoot it across snow and if it is spitting out unburnt powder you would see it in the snow in front of you...
But the real result of this is if it is working why fool with it... powder is not that expensive - results are..