Mine, a M28 6", and it was in the mid-1970's.
I was in my late teens, working p/t at a LGS and had recently gotten my first centerfire handgun, a Ruger Security Six, SS, 4" and soon thereafter also took up handloading.
Being young and stoopid, a friend and I began to experiment with +P+ .357 handloads.
An area Detective with our local PD who was an inveterate gun trader wanted that Ruger S6, as SS guns were a bit hard to come by at the time. He offered to trade even for his M28 6".
I viewed that M28 with all that beef in the cylinder, plus a longer barrel as a great platform for more nuclear .357 loads. We made the trade.
I'm ashamed to say, I tortured that M28 with stuff no one in their right mind should shoot.
It never showed any signs it was worse for the wear.
It went away on some un-recalled trade in the 90's.
Neat memories though.
Thankfully, that stage of handloading went away without me ruining any guns or hands or fingers.