He was holding on pretty good. He's an awesome shot with my 44 mags, even the "full house" ones.
But, he's now frightened of the "BIG GUN"...
You have to have a deep respect for these guns. The near-full-power loads will be 1 at a time for now on, no matter who's shooting them.
I tried a test myself yesterday. Full cylinder of the 700 grains. No double shots, but I did see that the third cylinder locked up because the nose of the third 700 grain bullet had pulled out of the deeply crimped case, and jammed the cylinder. That's the other reason for not trying more than one at a time.
Thank you all for your good thoughts and wishes. I love shooting with my son, and expect that we will share that enjoyment for many years to come.