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I agree on .357 Sig (or any necked case, but not sure how many .40 Super/.400 CorBon or 7.62 Tokarev carriers there are) suffering setback issues. Whether factory or handloaded, the bullet selection and crimp are both vital. 124 grain 9mm FMJ bullets with a graceful ogive cannot be made to magazine OAL with a failsafe crimp. You can dial in the OAL so that they cycle and crimp the heck out of them, but the bullets will eventually unseat given enough pressure or enough cycles through the chamber.

On the opposite end of the spectrum, the boxy, near SW style bullets (mimicing the old 158 and 180 gr .357 bullets developed for the then new .357 Mag) which have a sharp distinction between the ogive and bearing surface like HDY XTPs, can be made reliable with a good strong crimp. For factory ammo, nearly every manufacturer sorted this out a decade ago, but I have seen factory loads that I could push into the case with my thumb. Improperly done handloads with the wrong bullets or a weak crimp can and will suffer setback and either spike pressures or allow burning powder past the bullet, leaving it lodged in your bore (ask me how I know).

I would echo the advise that I have heard many times, which is that necked calibers in duty/carry arms should have the round in the chamber replaced with one from the magazine and placed in the bottom of the magazine when the weapon is cleared, which avoids waste of ammo and prevents setback. If I ever elected to carry a .357 Sig, I would probably use factory ammo due to the neck crimping issue.