Here are the bulk of the tests I said I would make earlier.
Powder Schuetzen FFFg. Primers Either Remington 6 1/2 or 9 1/2. Loading Density 100%, i.e., to the base of the bullet, no compression. Chambers are SAAMI std. i.e., for lever guns. Barrel length in ().
25/20 wcf (22.5) 15.6g 98g Lyman 25720 1252fps 17150psi
32/20 wcf (21.5) 17.0g 115g Lyman 311316 1154fps 6850psi
32/20 wcf (21.5) 11.0g 155g Lyman 311466 807fps 6850psi
32 Winchester Spcl. (20) 41.0g 178g RCBS 32170FN 1287fps 19750psi
38/55 (1.125case) (26.5) 39.0g 272g Lyman 375296 1216fps 12400psi
38/56 wcf (26.5) 50.0g 330g Accurate 38-325G 1282fps 19300psi
38/40 wcf (21.5) 31.0g 198g NEI 401200BB 1124fps 6200psi
44/40 wcf (23.5) 33.6g 230g Lyman 429434 1125fps 7400psi
At a later date I will also post for 30/30 & 33wcf.
One side note that I found is when the bullet sectional density goes up the standard deviation of both velocity & pressure goes down. This is not the case with smokeless. As I stated earlier I am a novice with black powder as I only shoot smokeless of which I have shot many thousands of rounds testing. So it was strange to me but maybe not to those familiar with black powder. I hope this is of some use to all interested.
Harry