Of my 2 .357 handguns, I have a 6" barrel S&W Model 27-9. The other is a 8" barrel 1980 Colt Trooper MKIII. So many variables (barrel length, bullet weight, caliber, powder), methinks I will start out with light loads of .38 spl and work my way up. Then start light on .357 mag. Would like to get...