I've been using 10grs blue dot in the 223 handi under 50gr hornady with great results.Just remember that whlie using blue dot for reduced velocity loads,that they are not reduced pressure loads,and like any max loads using any powder you must never try and push it by adding just one more grain or bad things wiil happen.That being said,I choose to use loads in the middle as thats what I wanted and have also use it in the 22-250.The loads match my full power ones accuracy at 100 yards and so far I have shot ground hogs out to 150 with no trouble.
So have fun,but be careful and safe!Let us know how itworks for you.