I was at Walmart picking up a box of .357 while being heavily distracted by my son. When I got home I realized I got a box of 125 gr jsp's. Should I be concerned about flame cutting with these rounds in my 4" 28? I'd rather not shoot them if it's an issue, but I can't take them back. Any info is appreciated.

Don't worry about it. 125's were a concern in K-frames, not N's. If they should do any cutting, it will not be deep or a problem.

A box shouldn't hurt. Flame cutting was more of a K frame issue, IIRC. I think 28s can handle just about anything (like 14gr of HS6... )

They are pretty rough on barrel throats over the long haul, though. One box more or less will not matter.

there will be flame cutting anytime you take high pressure gas and run it through an orifice which in ths case is the cylinder gap. it will go only so far and then stop. it will not affect safety. how long this takes to happen will vary for any number of reasons

I've put most of a box through my nickel-refinished 28-2. It takes me an extra patch or two to scrub off the residue above the gap, but I haven't been able to detect any damage to the topstrap.

Any magnum revolver will show flame cutting after it's been fired enough no matter how heavy the frame is.