After the post above, I did two separate work-ups with BR 5, one in my Black Hawk, the other in my Win 92, both in 45 Colt. I baselined with 7.9 grains of Unique compared to 7.9 of BR 5 and did 5 loads from each firearm. Below is what I did for the Black Hawk.
Previously I posted BR 5 data with my Win 92 in 45 Colt. This time I used a 7 1/2” barreled Black Hawk in 45 Colt. Jeff Bartlett gives initial guidance saying use Unique data. To get a comparison, I base-lined with 7.9 grains of Unique and a 7.9 grain load of BR 5, both using Lee’s 255 gr RNFP bullet. As a side note, 7.9 grains of Unique drops from a 1.02 cc Lee disk, 7.9 grains of BR 5 has a volume of 0.67 cc, the closest Lee disk is 0.66cc. If you were to use the Lee 1.02 disk, you’ll end up dropping 12.1 grains of BR 5. I didn’t go that far, but I feel it would be entirely safe in either the 92 or Black Hawk. Having no way of checking pressure, I considered ease of extraction, knowing that isn’t reliable with straight wall cases, and primer condition. No load resulted in a flattened primer, although I have a feeling I was approaching, or at +P pressures, but nowhere near Ruger/Thompson level high-end loads with 11.2 grains of BR 5. Five rounds were fired with each load. Most accurate load was with 11.2 grains of BR 5 which was no surprise given the low standard deviation.
Load Lee disk Velocity (f/s) SD
7.9 gr Unique 1.02 cc 887 14.93
7.9 gr BR 5 None (6.7 cc) 674 126.3
9.7 gr BR 5 0.82 cc 907 33.95
10.5 gr BR 5 0.88 cc 997 18.94
11.2 gr BR 5 0.95 cc 1095 12.4