Probably near max on their data and a shorter throat will increase psi and hold it longer down the barrel.Since I last posted in this thread I had a chance to try StaBall in my Sako 22/250 heavy barrel ( 24" ) rifle. Worked up to 42.5 grs with an Hornady 53 gr Match bullet in Laupa brass with a Rem 9 1/2M primer. Accuracy was good ( .5-.7) and velocity was 3803 ft/sec. Not close to the velocity cited by Hodgdon ( 3939 ft/sec) although they use a 52 gr bullet but fast all the same. JME