In addition to being a little hotter than current ammo, it was also taken from 8 3/8" barrels. 5" and 6" barrels, with factory barrel-cylinder gaps, cooled that off by something on the order of 150 fps, but it was still fairly warm. I suspect current powders can reach similar performance levels with a little less pressure. If Graybeard had used a steady diet of that stuff, he might have found out why the Model 19 was not considered durable enough and what lead to the 586/686.