Term for area between the Hi/Lo points of Trajectory?

[M4Fundi]

I had read somewhere and can't find it that there was a term for the the area between the Hi & Lo points of trajectory in reference to it being the effective kill zone above and below the line of sight. Anyone know this term?

[TiroFijo]

For hunting, and from zero to ?? yds/m it is often called "point blank range".

For other uses, and at any range (x to y yds/m) it is called "danger zone".

In both cases the size of the vital zone and the trajectory of the round fired determines this range.

[Wayne Dobbs]

Also related is the "beaten zone" in which there is a good probability of being struck anywhere on the body by rounds fired downrange.

[RWK]

I had read somewhere and can't find it that there was a term for the the area between the Hi & Lo points of trajectory in reference to it being the effective kill zone above and below the line of sight. Anyone know this term?

Are you thinking of the maximum ordinate?

[M4Fundi]

I always understood (and am often wrong;-) ) the beaten zone to refer to the area that you can reach at distance (usually behind an object or geographic rise) to drop in rounds using your knowledge of your trajectory and hit the enemy and was a term most used for machine gunners.

I had read and obviously can not remember a term for the zone that a rifle was zeroed that was its effective kill zone, kill zone being the wrong word but best I can come up with. i.e. a 50/200 Zero would have a (insert term) of 4.2 inches and a 25/300 Zero would have a (insert term) of 8. 9 inches...etc

So the "(insert term)" would consistently be 4.2 inches for a 50/200 Zero for brand x ammo using a barrel of x length and would change past the 200 yard (secondary initial point...another term I do not know and am looking for is what it is called when bullet crosses line of sight at second point)

I think I might call Hornady or Blackhills and ask

Thanks

[rat31465]

Mid Range Trajectory and or Point Blank is how I have always heard this defined.

[TiroFijo]

To further illustrate:

for a Sierra .308" 175 Match King HPBT @ 2680 fps, sight height 1.85", std. conditions:

20" diameter vital zone

max Point blank Range (PBR): 400 m, zero at 339 m

but, if you have the rifle zeroed at 200 m your PBR is now only 298 m

Now, if you have the rifle zeroed at 600 m, your vital zone is 20" and you hold on the center of it, the danger zone to strike this target is between 568 and 628 m.

[DBR]

The RCBS ballistics program calls the line of sight crossings "first and second zero distances". I have also heard them called "near and far zero".

The combined distance above and blow the line of sight that is used for point blank purposes is simply called "target diameter".

The allowed "target diameter" is what determines the zero crossing distances.

[RWK]

I always understood (and am often wrong;-) ) the beaten zone to refer to the area that you can reach at distance (usually behind an object or geographic rise) to drop in rounds using your knowledge of your trajectory and hit the enemy and was a term most used for machine gunners.

Here you are:

Beaten Zone. This is the pattern formed by the rounds within the cone of fire striking the ground or the target. The size and shape of the beaten zone changes as a function of the range to and slope of the target. Gunners and automatic riflemen should engage targets to take maximum effect of the beaten zone. The simplest way to do this is to aim at the center base of the target. Most rounds will not fall over the target, and any that fall short will create ricochets into the target.

[rat31465]

http://en.wikipedia.org/wiki/Field_of_fire

This is a link to wikipedia for the term Beaten Zone.

The Beaten Zone is a concept in indirect infantry small arms fire, specifically machine guns. It describes the area between the "first catch" and the "last graze" of a bullet's trajectory. At the first of these points a bullet will hit a standing man in the head, at the last of these points, as the bullet drops, it will hit a standing man in the feet. Anyone standing within the beaten zone will be hit somewhere from head to foot.

The concept works best as part of a static defence with the area covered by a position plotted out beforehand. Usually the machine guns will be mounted on a tripod and indirect fire sights (such as a dial sight) fitted in addition to, or instead of, direct fire ones. Fire can then be called in by spotters to engage specific points in the guns field of fire, even if out of sight of the machine gunners.

Overlapping machine guns, creating a crossfire, using the beaten zone concept, together with the idea of enfilading were an important part of World War I.

Beaten zone can also refer to the area that shells will usually land in when fired from an artillery piece. It is in the shape of a rectangle with the longer sides parallel to the direction of fire because artillery tends to deviate more forwards and backwards than right and left.