Black Powder for .357 Mag or .38 Special

Has anyone out there loaded black powder loads in either of these calibers? My CAS guns are Uberti Cattlmen 5.5" .38 special or .357 Magnum and tend to shoot high so lighter bullets and hotter loads bring them to point of aim. I prefer to use .38 cases as my Rifle has an 18" barrel and to load 10 rounds I have to seat the bullets deep (1.540) in .357 cases, which is OK for CAS but prefer to load everything to spec. I have been using 125 RNFP over stout Trail Boss or Unique but would like to give Black powder a whirl. I have a brass drop tube and am also wondering about a funnel. Is aluminum OK or do I have to hunt up a brass unit?
Thanks......Horsetrader Jack
Ps: If anyone is looking for a great price on Quality cast bullets give Rose at Second Chance Bullets in Vancouver ,Wa. a call (360) 696-4999. They are top quality and an example of price is $52.00 for a 1,000 125 grn RNFP .358 diameter and she can fit 3,000 in a $10.00 if it fits it ships box. They are top quality with NO leading problems and she can cast up to a 428 grain 45-70 bullet. Be sure to tell her Horsetrader Jack from Medical Lake sent ya.