Guns: Model 640 Pro 2 1/8" and Model 642 1 7/8"
Bullet: Federal 130 gr HST
Case: Federal 38 special
Primer: CCI-500 small pistol
Overall Length: 1.18"
Five shots @ 25 yards benchrested
Chronograph: Oehler 35P 10 feet to center of screens


4.1 grains Winchester 231
Pistol Velocity Std Dev Energy Group
Model 640: 854 fps 8 211 10.2"
Model 642: 815 22 192 16.0"

4.8 grains Alliant BE-86
Model 640: 840 fps 18 204 9.1"
Model 642: 832 12 200 9.0"

3.8 grains Hodgdon Titegroup
Model 640: 836 fps 16 202 8.9"
Model 642: 833 23 200 7.6"

My goal was velocity between 825 and 850 which is close to what I've found online for actual Federal factory ammunition in a 2" revolver. All of these loads met that goal in my revolvers.
Accuracy, however, is a whole new issue. In short, W-231 is awful. This test is the final result of several rage sessions and W-231 was just as bad in other shoots. The reason I used the M642 was to see if the poor performance was due to the gun or the load.
The other problem I found is that the center of impacts for most loads were as much as a foot below the point of aim. This shouldn't be a problem if the intended use is for a bad guy at a maximum of 1-3 yards.
I'd like to try other powders but this is what I have on hand to use. Our Sportsman's Warehouse has had zero powder of any kind the last four times I've checked. Same for pistol primers.

Please keep reporting your results with these oddball bullets and maybe we can build a database of good loads for them.

I am surprised that the longer .357 Pro cylinder was getting higher fps in your test....... maybe a better gap/tightness ?

Those figures are in the ball park.
My same load of w231 in my M49 got 805 fps but it had a OAL of 1.22", for my first try with this new bullet.
Unique puts out a little more fps than the BE-86 in my test per powder weights.

I don't have TGroup but with the same powder amount I can match the M642 833 fps with Green Dot powder.

I have w231, Unique, Blue Dot and Alliant Steel powders on my next test. I am only trying Steel since the slow 2400 powder was a dismal failure in the fps loads and have 8lbs of it.
I have not tried Blue Dot yet, with the 130 HST but BD did well in my 686 6" in 38 special with 110,125 and 140gr JHP bullets, with a lot longer OAL , though !!

Like you, the loads will be 1.18" oal with one at the long 1.43" which was very accurate on my last test.

Later.