There are a few things I would like to point out here...
First off, many people
freak out about reloads, and one group of folks that often freak out as much/more than anyone are
reloaders. It will be up to you to judge which advice is overly emotional and seemingly "doomsday."
For certain, some truly horrendous results can come from bad, reckless, careless or dastardly handloading. Of this there should be no doubt, but I believe it should be approached with some detective work.
The easiest answer would be "By golly, I would never go near anyone's reloads, for goodness sakes!
" To that, I say WHATEVER. If that is the kind of world that one must live in, staying out of cars and off public roads, away from swimming pools and five gallon buckets and for certain, avoid hospitals and doctors/surgeons at all costs. If pure safety is the goal, those are far more dangerous activities than shooting someone's handloads.
Do the detective work. What does the brass look like? Do you have a dial caliper, can you measure the length of the loaded cartridges? Does every single one of them look exactly like the last one and the next one? Is your friend the type to pay close attention to details? Can you chamber each and every round without any resistance and do they all easily fall back out of the chambers without help?
You could spend $15 and buy a kinetic bullet puller and break down some of these rounds and measure what is in them yourself.
Why has he given them to you? Most handloaders don't give away .357 brass, that stuff is not something we find everywhere. Or did he give you the ammo with the expectation that you would return the brass?
Knowing that there is variation in weight from bullet to bullet and from cases to case, if you knew for a fact that the powder and powder charge was 100 percent accurate, and the cartridge length was correct, would you assume these reloads were safe?
If I knew the person that assembled them (and he passes the sniff test) and the weights you reported were my data set, then I would confidently say "YES", I would reasonably assume those loads were safe.
Those are very light loads by any measure. In a .357 Magnum revolver, they barely eclipse .38 Special, and .357 Magnum runs a full TWICE the pressure of .38 Special.