DO THEY SAY 357? I mean ONLY 357 mag dies? What brand are they?
I have seen 38 Special dies, and 38/357 Mag dies. But I haven't seen just and only 357 Mag dies... (Read a little further OR go to company web site with die model number. I'll bet they are made for 38/357 mag.)
If ONLY 357 Mag, then I agree with wncchester, it will still re-size the 38 case, but , belling, seating and crimping will be the problems. They can be adjusted for the MAXI tho..
CW