I did a similar hunt last fall and let me tell you, most potential shots were not in my comfort range for a revolver, even with a long barrel sight radius. I was thinking 50yds would be the norm. They weren't, it was more like 75-100yds and the hogs we were watching didn't stop moving long enough to get a good shot off.
I had thoughts of taking my 629-4 8 3/8" with open sights but ultimately I opted for a rifle, a 1895GS. The last week before the trip I broke down and put a scope on it. I made the right choice, with lighting conditions when we hunted early in the morning a handgun would have given me a strong disadvantage.
Even with the 45-70 I had a nice 250lb+ boar run off and we had to track it. Found it again, still alive and well, shot again through the shoulders and it ran off again but dropped about 50 yds away. Both shots fully exited but the first was too high to do any real damage. Both shots I could have never made with a handgun and I would feel very underpowered with a .357.
That being said I shoot a home cast 180 grain WFNGC bullet out of my Rossi 92 with 14.5gr H110. I have not shot any of these out of a revolver so I'm really not sure how hot they are. I would start with 13.5 grains and if it doesn't seem too crazy don't be afraid to work up a little.