No. That's precisely what it doesn't handle well.
When you have one or two "shots" per turn at say 5th level that deal 1d6 or 1d8 you're not simulating guns. I don't know what you're simulating, but it isn't bullets. Even a "crit" with a gun is so minimal damage as to make a mockery out of the lethality of firearms.
See, posts like this are why firearms rules are complete nonsense in most D&D-derived works. They're not magic death wands.
If you get a bullet in the brain, heart, or lungs you are probably going to die in a matter of seconds. If you get a bullet in the intestines, without medical attention, you are probably going to die within a matter of days. Take a hit anywhere else... well... you're just not going to die at all.
They're a lot like daggers, really.
Main difference between the two is that a non-lethal firearm attack is somewhat more likely to cause permanent, debilitating inuries-- the kind of realistic injuries that the D&D rules deliberately do not model.
There is no point at which D&D's modeling of weapons and injuries even approaches realism. Firearms only appear to be more unrealistic because we are more familiar with their portrayals in the media.