Was able to get out to the range with my chrono and SP101 today!
I did some probing with powder choices in .38 +P with Speer's 135 GDHP.
6.8 AA#5 with CCI 550. Avg 837 with ES of 75.
6.4 Power Pistol with CCI 500. Avg 910, ES of 76.
7.0 HS-6 with Rem 1.5. Avg. 832, ES of 56. Acceptable ES, lower velocity than I hoped for. I will bump it up from 7.0 to 7.2 (max) and see if that gets me the 30 fps I'm hoping for.
Not really liking AA#5 in any of the .38 loads I've tried so far. I will give it another shot with std. primers and the max .38 load, both with 135 GD and 158 LHP.
HS-6 was disappointing with 158 lead, but shows the most promise with 135 Gold Dot. I used standard primers with the 135 but magnum with the lead. I might go back and try standard primers with lead.
Power Pistol definitely has more flash, bang and roar! Seems to have wide ESs all around though which is disappointing.
I tried a random load for fun that I think will make a great camping/hiking load in .357--180 XTP (hollow point) 12.0 grains 2400 with CCI 500 primer. Avg 972 with an ES of only 27! Subsonic with a heavy hollow point bullet that hits exactly at POA at 10 yards.
In closing, I haven't found a great FBI load duplicate yet...