Somebody has to at least try to keep you in check. Lost cause I know, but you know I have to razz you for old times sake.
No I am NOT going to say you should have bought a 38SPL barrel... although my very first Contender frame came with an 8 3/4" octagon, and I simply loved it. It's the only barrel I ever came close to wearing out even though I only shot cast target/plinking loads in it - probably hundreds of thousands of them over those early years with a buddies help. Sessions were at least one, sometimes two 5 gallon buckets full of reloads to keep me (or us) happily banging away from dawn to dusk over several years.
If it were me that wanted a light/quieter load way back when I still had a 357Max , I probably would have simply loaded it down with an appropriate powder, used filler if necessary, maybe tried a duplex load or just went ahead and shot my 38SPL ammo of choice in it. You know and I know you won't keep the barrel long enough to worry about it either way anyway, so do what fits for you.
You crossed the bridge way back on making your own Contender barrels... do remember you having a bunch of barrel recoil blocks. I also remember discussing with you both them and also simply "rebarreling" factory barrels since you do have the equipment to do it. It's been done for years by others, has worked fine on all I shot or heard of for reasonable cartridges, might even work fine for the biggest, baddest cartridges (although I would have never had a need to find out with all of the handcannons I wanted in custom barrels). Simply acquire a donor barrel used, whack the barrel appropriately ahead of the barrel block, re bore the stub and chamber, mod the new barrel blank to install in it any of at least 3 ways (depending on what from and what too), rechamber/do the extractor and you have just about any of the 275ish cartridge choices you want for your Contender. With the rebarrel work that I know about you have done it ought to be easy enough for you to do. Would whet your lathe appetite just fine as it's almost all lathe work.
FWIW the 25-35 works quite well in the Contender as is, even with handgun lengths thanks to so many better bullets and powders coming available since it's start. Mine was a factory handgun barrel, was great for predator hunting just as is, and I'm sure could have handled at least big mule deer just fine to reasonable ranges if I had ever tried it for that. My 25's of choice though as a mostly handgun hunter were the 257JDJ's, and the 25-20WCF, 25-21 and 25-25 Stevens were also favorites for my uses for the caliber in Contender's. The 25 "to do" cartridge left undone on my list when I stopped shooting was the 25 Classic. I had a large stockpile of Starke RPVB 82's I wanted to shoot up in something new, and I thought tossing them around 2900 way down range with a 25 Classic handgun was just the ticket for them. Never got my 30 Merrill Contender barrel either, another excellent choice for the 1000 new 225 Win brass I still have left over from the JDJ days and thousands of 125gr TNT's. Had some others on the list, but these two just kept saying "must do" to me. But I had too many other irons in the fire to get to them, waited too long and ran out of time.
