[Sevens]

I don't, and have never, picked a powder based whatsoever on the length of barrel I may shoot the ammo in. In fact, I'm typically going to be making ammo that runs in MANY different guns. I love the idea of having different loads for different purposes, but I think it's a little nuts to try and tailor simple handgun loads to each different, specific firearm. (Rifle is a different story!)

.38 Special is a low pressure round. It's going to run best with a faster burning powder. I've had good luck running 158 grain bullets with Titegroup and Green Dot. I can use Universal and it runs well and gives good accuracy, but there's unburnt flakes and they always end up everywhere, and it's an annoyance (and more!) with scuzzing up a revolver.

I have some extreme .38 Special loads running a 125 grain bullet and they run balls-to-the-wall for .38 Special, so I only run them in modern guns, typically in .357 Magnum revolvers. Actually, in the interest of full disclosure -- I built the load to run my Coonan pistol with the included (very light) 10-lb recoil spring. No wimpy .38 loads will run a Coonan, so these loads run the very ragged edge of what can still be called a .38 Special+P. For that load, I get great performance out of Power Pistol.