Bullet attitude

[waksupi]

We were having a discussion at work today, I believe may have been covered here before.
As a bullet approaches a target at extended range, is it approaching at the same angle of flight, as when it left the bore? Or is it nosing down?

Another unrelated question, who makes good benchrest actions?

[Bullshop]

OK OK Im gona vote for same as when it left, so when it hits the ground it hits on its side not its nose.
BIC/BS

[dragonrider]

The bullit will hit nose first. Think of a football when thrown with a good spiral. It is the action of the spinning which keeps the bullet or football in the nosefirst attitude.

[felix]

When it touches the ground, it will MOSTLY be on its side, if shot less than say 45 degrees. ... felix

[felix]

There are quite a few BR actions which are noteworthly. ALL are far better than factory in terms of fit and stability. ... felix

[Tom Myers]

A ballistics question usually has an answer that begins with, "It depends" and this is no exception.

If a right hand twist bullet is well stabilized, it will follow a shallow -curve trajectory with the nose pointed slightly upward and slightly to the right of the initial path.

We know that when pressure is applied to a spinning gyroscope, the gyroscope tends to move at a right angle to the pressure,

That right inclination of the bullet's attitude is caused from air pressure on the bottom of the gyroscopicaly stabilized bullet deflecting the bullet's axis towards the right. This results in the right hand drft referred to as Spindrift.

If a bullet is "Overstabilized" (Spinning too fast) air pressure on the lower portion of the bullet will not be enough to overcome the gyroscopic force created by the high spin rate and it will indeed fly nose high, striking the target at an exagerated angle to the trajectory.

If a bullet is "Understabilized" (Not spinning fast enough) the air pressure on the lower portion of the bullet will tip the axis of the bullet toward an attitude that will more closely follow the path of the trajectory. However the low spin rate of the bullet may cause the bullet to become unstable, precess around its axis and eventually tumble.

If a well stabilized bullet is launched at a high angle, or vertically, then generally the air pressure on the bullet profile will not be enough to overcome gyroscopic force and the bullet will strike with the base down.

The whole process is far more involved than these few statements, but hopefully they are more enlightening than confusing.

Hope this helps.

Tom Myers
Precision Ballistics and Records (http://www.tmtpages.com)

[felix]

Perfect, Tom! ... felix

[KCSO]

I have no science here just a comment...
At the Sandy Hook tests in the 1880's the recovered BP bullets fired at extreme range were recovered point down in the wet sand. All the bullets I have recovered from roofs and building tops were buried in point first. Ask Mythbusters, it looked to me like the bullets fired straight up still came in point first, but I would have to re watch and stop frame it to tell.

[felix]

KCSO, that would indicate a perfect twist rate at that range, and that the boolits were shot up at around 45 degrees or so. Point down, yes, but not straight on as implied. ... felix

[MT Gianni]

There are a lot of very smart folks on this board that passed 5th grade and could care less whether the proper spelling is mould or mold. Thanks for your expertise, Gianni.