I can tell you for sure that it helps with follow ups, especially with light weght snubbies. When I use to play with the idea, I’d load 38-357-38-357 and a fifth round would be a hard cast bullet in case I had to fire thru cover. I can assure you it won’t hurt the gun, but I still recommend more practice with 357. I’m actually more accurate with 357, and my follow up time is fine. I still like the 5 round to be hard cast just in case. Another option is to try a hot 38+P. Underwood and Buffalo Bore both make some +p stuff that actually reaches low-end 357 power, but cuts back on the flash and flip a bit over medium to hot 357 loads. Not what I carry except in my bedside gun, but probably oneof the best ways to go for snubbies, If I carried one of the real light weight guns, I’d go exclusively that way, but I prefer heavier all steel guns and have no problem with 357 in them.