Thanks everyone.
I like to put at least 100 rounds of carry ammo through a new weapon before I start carrying it.
I also want to adjust the sights if needed.
Thanks again.
PS-My main carry gun is a 642-1 with Golden Saber +P. It's a handful too with that ammo.
I suspect the S&W engineers are relaying on the individual shooters' pain thresholds to limit the round count of .357 Magnum ammo put through a J magnum frame .357 Magnum.
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As for putting 100 rounds through a handgun before carrying it for personal protection, that is probably not enough for a semi-auto pistol, and it's probably more than is needed for a revolver.
If you're going to encounter problems with a revolver with a specific self defense, it'll be sooner rather than later.
You can also maximize some aspects of it, such as ensuring rounds do not start backing out of the case, by shooting 4 of the 5 rounds in your J-frame then reloading, and indexing so that the 5th round is again left unfired. Rinse and repeating until that one round has been exposed to the recoil of 15 and then repeating it with a couple more rounds will pretty much guarantee that the load isn't going to back out and jam the revolver.
You'll also want to check to ensure that your self defense load doesn't leave lots of unburned powder grains, one of which can get under an ejector star and prevent a reload if needed.
In a short barrel J frame (3" or less) .357 Magnum, the maximum loads of those slow burning powders that create this risk also tend to generate velocities about 100-150 fps less than a maximum load of a medium burn rate flake powder, so they offer no real world benefit. The faster burning flake powders won't get under the ejector star and create enough of a clearance problem to prevent a reload so it's a win-win in a J-frame .357.
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The focus instead should be on a program of recurrent practice with your carry ammo - cycling it out of your carry rotation every time you go to the range (every week or month at the most) by expending it down range, along with a healthy amount of general practice with .38 Special.