As the subject line says, I want to know what point blank range means? I know roughly that it means really close range, but not precisely what it means, or who uses the term (in what context), and where the term comes from. Any other bit of information you want to throw in would be good too.
My guess would be that it’s the range at which an unskilled shooter would still be pretty much guaranteed to hit the target. Spitting distance, basically.
Point blank is damned close. Technically it is when the line of sight down the gun tube and the trajectory of the missile are the same. It means that the gun is close enough to the target that the bullet, or ball, or shell, will not be appreciably affected by gravity in its flight to the target. It is closer than “don’t shoot until you can see the whites of their eyes.”
Here is your answer and a good site for this sort of question.
As I understand it: Whenever you fire a gun, the bullet will end up slightly lower than where the muzzle was pointed, due to gravity. Gun sights try to compensate for this, by angling down slightly. However, since the path of the bullet is curved, and the line of sight is straight, this correction will only be exact at one particular range. That’s point blank range. Hopefully, a gun person will be along shortly to elaborate and/or correct this.
Or, it’s within 30 feet, and if you have the appropriate feat you get a +1 to attack and damage rolls.
You may be right, Chronos, but the muzzle velocity of even a very heavy artillery piece is fast enough that at “point blank” range the drop is negligible.
I have also seen the term used to describe a more modern practice known as barrel-sighting. Quite simply, you open the breach, train the barrel so that you can see the target through the muzzle, then load and fire.
According to Stephen Ambrose in Citizen Soldiers (which may not be the most reputable work these days), when American soldiers fighting in Europe got fed up with some Germans holed up in a difficult to assault building, they hauled up a self-propelled 155mm howitzer and sighted it against the building in this fashion from maybe four blocks away. Apparently the concussion from the muzzle blast augmented the overall effect. After just a few shots, the Germans surrendered, calling the practice inhumane.
That’s the last example I can think of of actual point-blank artillery firing, but I’m sure there are more recent ones.
With a nuke id say about 10 miles 
jon, though I know it was facetious, I feel like responding. 
It really depends on the nuclear weapon you’re using - smaller weapons might actually only be lethal (from the explosion, not secondary effects) for a kilometre or so. I’m not quite sure on how small an atomic bomb can be and still explode (that is, attain critical mass)
Damn close. The ballistic trajectory will intersect the line of aim twice, once as the round is rising above the line, and once while it is coming back down. For the M16A2 I seem to recall 200m and 25m being the two points.
Generally the term is used to mean “close your eyes and you can still hit the target”. Technically, Chronos is on the right track. For example, for a rifle that is “naturally” sighted in at 100 meters, the line of sight and the line of fire, which is the path of the bullet, intersect twice. Once, very close to the muzzle as the bullet path is angled upwards, and again, when it is on a downward trajectory, in this case, 100 yards. In the technical gun world, point blank range means the longer one. When the downward trajectory meets the line of sight. In common usage though, it sort of refers to the upward trajectory… the “no aiming required, just point and shoot”.
So in a way when the bullet’s parabolic curve intersects the x axes? Put it in a way I can understand :p.
Very few gun sights are static. Almost all guns have range adjustable, and most have windage adjustable sights. So there’s no particular range gun sights are set for - they’re set for whatever you want them to be set at. It’s possible that the term point blank refers to the exact range the weapon is sighted in at at any given time, but that seems unlikely, because it can as easily be 50 yards as 500.
+1
websters
Point-blank \Point`-blank", a.
1. Directed in a line toward the object aimed at; aimed
directly toward the mark.
Assumably, then, point blank is the range at which range-corrective sights do not have to come into play, and one can bore sight the weapon accurately enough.
Not to be confused with point blank verse.
I thought Pointe Blank was a movie with John Cusack and Minnie Driver? Or, is that just a Grosse example? 
Here’s what happens:
Let’s say your gun sights are “zeroed” for 100 yards, and you’re shooting at a target that is 100 yards away on level ground. (I’m obviously assuming a rifle or shotgun here.) When the bullet exits the barrel, the direction will not be parallel with the ground; it will be rising. As it continues to rise the bullet will intersect the line-of-sight[sup]a[/sup] a few feet in front of the muzzle. It will then reach a maximum height at around 60 yards or so, then start dropping. At 100 yards it will have dropped to the point that it has (once again!) intersected the line-of-sight. This, of course, is where the target is.
[sup]a[/sup] Line-of-sight is the imaginary, straight line that intersects the front sight, rear sight, and target.
According to the 1863 Robert’s Hand-Book of Artillery:
And it goes on to say
So apparently the definition varied between different armies, at least at the time of the Civil War.
The whole handbook (a large work) may be read at:
http://www.civilwarartillery.com/books/RobertsHandBookofArtillery.htm
And don’t get me started about obturation!
In the context of artillary and warfare, then Chronos and Rod Hill nailed it, but in the context of murder mysteries, Quincy and CSI, point blank means “at the end of the barrel.” Then there is talk about powder burns on the victim’s clothing to indicate the closeness…
In March of 2000, right here, inky asked, “Anyone know the origin of the term “Point Blank” as in close range (“He was shot Point Blank”)?”
http://boards.straightdope.com/sdmb/showthread.php?threadid=27488&highlight=point+blank