I did indeed try the Sam Fadala load of 31 gr. of H4198 as well as another suggested load of 32 gr. of RL-7. BOTH loads gave velocities of about 2000 fps. I don't have the data here at work with me but I think they were within 50 fps of each other with the same bullets. I also tried them with the Barnes Original (you would use the .377" but I used the .375") and got the same performance and case head expansion.
Sam apparently uses both the Barnes and the factory bullets (which he pulls, then dumps the charge and then loads with his own charge). I would prefer the Barnes at this velocity if using this load on bear. The factory bullets are built for the 1300 fps range AND for deer. I don't think I'd be happy with penetration when started at 2000 fps but the Barnes is more heavily constructed and should do fine.
The load I decided to use is the RL-7 load of 32 gr. It apparently produced less pressure and was the faster of the two loads. Might be picking nits, but I liked it better. I used CCI LR primers and was careful to trim my cases and to use a slight roll crimp. This generally works well.
I've been using the Cast Performance 265 gr. GC but only with 28 gr. of IMR 3031 which gives me about 1560 fps (if memory serves). I would think that about 30 gr. of RL-7 or IMR-4198 (up to you to work this up in your gun) would go about 1900 fps. Of course it has to fit or it will lead the bore.
I've gotten Dave Deering (Stone Fence) of FL to make me some of his bullets and they are outstanding!
I like my Contender because I can switch back and forth and only need to buy an additional barrel (without additional firearms purchase, at least in my jurisdiction). The .38-55 is fully the equal of the .375 Win.
One other note. The Hornady 220 gr. .375" bullets will probably NOT work in your .38-55 as their form is incorrect to work with the .38-55 case and throat(s). I don't know about the Sierra.