I tried T7 just once and got a five inch group from a pistol which goes 1 1/2" with Goex 3f or Pyrodex. It's also very prone to misfires and hangfires. Black is the cheapest powder and if you buy at least five pounds with the hazmat fee it will still be cheaper than most of the substitutes. Grafs is a good source. I've also gotten very good accuracy with Pyrodex RS, although it says it is for rifle and shotgun it works just fine in revolvers too. Most of the substitute powders other than Pyrodex have a limited shelf life once opened. They draw moisture, clump up and loose power with age. Black powder is the real deal, the substitutes are, well, just substitutes. Firearms would never have developed if blackpowder had not come first.