hawkins,

With all due respect I believe you might be misunderstanding/confusing some points.

Whenever the velocity of a bullet in flight deteriorates, by whatever means, the time of flight increases and therefore all forces acting on the bullet (gravity and wind especially) will have a longer time to act and the result will be a greater effect of those forces.

Every book I have ever read on ballistics says this, albeit, using different terms at times. I read absolutely nothing in Vaughn’s book on this topic that wasn’t also said quite clearly by Robert Rinker and Art Pejsa in their books on ballistics. Both of these men are also engineers specially trained in ballistics and aeronautics.

That’s why I asked the question of why you considered Vaughn’s statements on the effects of wind to be so special and/or ground breaking.

If there is one constant that all of these men agree upon, and point out in their writtings, it is that the most important factors in combating wind deflection are the ballistic coefficient of the bullet and the velocity...with bullet weight playing an important role also. All of these factors allow the bullet to retain its velocity longer, and therefore reduce its time of flight, which in turn reduces the amount of time any force can act on it.

Read any book on ballistics, by any writer, and their final conclusions are always the same on this topic...even though they may arrive at those conclusions in slightly different ways.

Heavy bullets with high ballistic coefficients, driven at high velocities, will be effected by cross winds far less than bullets with any of these three things that are lower...and that‘s pretty much all that shooters need to be aware of. This is proven by mathematics, physics, computers...and most importantly, real life situations.

It’s kind of like that old saying: “I don’t need to know how your watch is made...just tell me what time it is!â€

Rick0311, You have not read either my post or Vaughn's book (pg 195 "wind drift").
Drift is not proportional to the time of flight, it is proportional to the velocity lost.
Befor you lose thr rest of your credibility, borrow the book and read it.
Good luck!

quote:

Originally posted by hawkins:
Rick0311, You have not read either my post or Vaughn's book (pg 195 "wind drift").
Drift is not proportional to the time of flight, it is proportional to the velocity lost.
Befor you lose thr rest of your credibility, borrow the book and read it.
Good luck!

hawkins,

I have had his book for quite sometime and it is sitting right next to me as I write this.

Perhaps you would be so kind as to explain how “loss†of velocity does not effect time of flight? If a bullet is losing velocity (slowing down) does it get to the impact point sooner or later than if the velocity had remained the same or had been lost at a slower rate?

I read your post and understood everything you said and merely asked the question as to why you considered Vaughn’s statements as being so different than every other book written on the subject of ballistics. I do not find any basic differences in Vaughn, Rinker, or Pejsa’s chapters on the effects of wind on a bullets path...and I own and have read all of them.

I’m not sure what credibility I have lost...but since you seem to have given yourself a huge amount perhaps you can loan me some?

hawkins,

From page 199 of Vaughn’s book: “This means of course, that one should maximize muzzle velocity and ballistic coefficient for minimum wind drift.â€

From page 277 of Rinker’s book: “The ballistic coefficient and high velocity are the main factors in cutting wind deflection.â€

Do you find any conflicting information in these two statements?

rick0311, of course loss of velocity does affect the time of flight, but not in direct
proportion. If you have a problem with this borrow a high school math book. The drag is what Hatcher called "retardation".
I'm going to drop the subject, it's a waste of time.
Take Care!

quote:

Originally posted by hawkins:
rick0311, of course loss of velocity does affect the time of flight, but not in direct
proportion. If you have a problem with this borrow a high school math book. The drag is what Hatcher called "retardation".
I'm going to drop the subject, it's a waste of time.
Take Care!

hawkins,

I wasn’t trying to start a fight or get your panties in a bunch...I just asked you a question that you have still not answered.

It sounds as though you are assigning some huge significance to rifle bullets as if they are somehow different that any other projectile in flight.

The natural forces acting on projectiles in flight don’t know, and could care less, if that projectile is a bullet, a football, an arrow, a rock or any other damn thing. They act on every object the exact same way...and the longer they are allowed to act on it the more pronounced the effect will be.

I’m sorry if that confuses or frustrates you, but your confusion and frustration has no bearing on the accuracy of that fact.

Rick0311, This is against my better judgement;
It is accepeted as fact that "Wind Drift" is a function of the velocity lost, not the time of flight. That is why a High velocity 22 will drift more thana standard velocity one.
Now be still for a moment and ask yourself why that should be.
Take Care!

quote:

Originally posted by hawkins:
Rick0311, This is against my better judgement;
It is accepeted as fact that "Wind Drift" is a function of the velocity lost, not the time of flight. That is why a High velocity 22 will drift more thana standard velocity one.
Now be still for a moment and ask yourself why that should be.
Take Care!

Hawkin,
I'd like to hear more on this, as this is not what I understand as "Accepted as fact"...

while I don't have a fully vetted function or model on this, it stands to reason that
1: wind (we'll use the SAME wind) exerts force of X
2: bullets have inertia

Newton's First Law states that an object will remain at rest or in uniform motion in a straight line unless acted upon by an external force. It may be seen as a statement about inertia, that objects will remain in their state of motion unless a force acts to change the motion. Any change in motion involves an acceleration, and then Newton's Second Law applies and that is the little ole f=ma thing...

So, it would be possible that the ammount of force exerted on EVERY bullet fired in identical conditions has exactly the same force applied, but the M and A parts affect the F...

in other words, a heaver and/or faster bullet will have LESS "drift" than a lighter and/or slower bullet, assuming that condition A has a higher inertia than condition B.

Or, in some other view.. the amount of drift in a bullet will be the effect of the wind's F factored over time vs the bullets inertia.

i think this is pretty basic stuff, and would like to understand where I am wrong

jeffe

Rick0311, I didn't answer your blurb;
It dosen't make any difference if the object is a rock ect.". Of course it does, a bullet is spin stabilized and will adjust to the wind. That difference is what makes a rifle.
Take Care!

jefeosso; The point is that the wind does not "blow against the side of the bullet".
The gyroscopic effect of he rotation turns the bullet into the wind such that the combined wind speed and bullet speed are directly on the point. This causes the bullet drag to have a component down wind that causes drift. Any effect that reduces drag will reduce drift.
The reason I mentioned this to begin with it that after 50+ years or reading "gun stuff" Vaughn gave me the first reasonable explaination. A similar misconception exists as to the effects of shooting up or down hill. Must gun writers get it wrong.

Take Care!
Good luck!

Know lets see from what I'm told an M1 Abrams or some artillery guns accuracy in terms of MOA will make a Benchrest Shooter hang his head in shame. So someone must know what they are doing at Aberdeen or wait isn't that where Harold Vaughn worked.
Now lets see M1 Abrams, smooth bore, solid, fin stabilized projectile, muzzle instrumentation, how about the breech threads probabably buttress, acme or square? I wonder if Vaughn was looking over someones shoulder with all those ideas?[/QUOTE]

I believe that cannon is German, originally developed for the Leopard I or II tank.

hawkins,

Standard .22 LR ammo is effected by the wind more than .22 LR Match ammo because the standard ammo has a velocity that falls in the transition range of Mach 1.0.

The Drag on a projectile in flight in this range is increased disproportionately and the bullet is literally “delayed†(read that as longer time of flight) in this area and the wind effects its path more so than if it had not been delayed by the drag from the increased air turbulence and the huge pressure changes at and just above Mach 1.0.

Remember the movie All the Right Stuff? Remember what happened to Chuck Yeagar’s plane the first time he approached and then exceeded the speed of sound?

I understand, and agree with your statement in principal. Where I part with your views is when you state that the “ONLY†factor to consider in wind deflection is the loss of velocity...if I am interpreting your statements correctly.

I believe that loss of velocity is “one†of the factors to consider...but in doing so you cannot divorce yourself from the many other factors that contribute to that such as bullet shape, overall BC, weight, initial velocity, etc.

Again, I have no real problem or disagreement with your statements, I just inquired as to why you considered Vaughn’s work as being so much different from the work of the other people I mentioned. I read them all and find no real difference in their work or their conclusions on this topic.

Tbe Ballistic Coefficient is based upon velocity loss (retardation factor).
Drag is related to BC by velocity.
The bullet has a downwind drag.
Wind does not blow on the side of the bullet.
Drift is controlled by BC, BC is controlled by
velocity loss.
What else do you want to change?
Good luck!

hawkins,

I don’t recall trying to “change†anything, and I also don’t recall saying that wind deflection was caused by the wind “blowing†on the side of the bullet.

All I have tried to say is that velocity loss is but one factor (yes, an important one) in the equation...NOT the only one as you have claimed.

I have also stated that loss of velocity results in a longer time of flight...which you seem to totally discount.

Your example of .22 LR ammunition is a very poor one because projectiles moving in the transition area of Mach 1.0 are subjected to forces that super sonic and sub sonic projectiles are not.

Perhaps a simple way to express my view is to state that: all other things being equal, a bullet that is in the wind for a longer period of time (for whatever reason) will be deflected by that wind more than a one that is in the wind for a shorter period of time.

Hawkins,
in the spirit of debate (not picking a fight for certain)

if one drops a rock in a vaccum, other than earthly rotation, it falls straight down towards the center of gravity pull, right?


if there is a huge fan (wind tunnel?)blowing it moves with the direction of the air flow right?

this ammount of movement can be explained by f=ma rather eaily, as the rock is accelerating 32ft/s/s

repat the same experiments with a gryoscope, even the kids toy of a pull string 'scope...

the movement is LESS but still in the same direction.

Okay, let's add a forward vector... launch the rock, twice again, at 1000 fps..

(this part is psuedoscience, c i don't feel like doing the math)...

the rock REPEATEDLY moves the same amount, in both condition, viz no left/right in no air current, and to the left if the wind blows from the right.


now, the gyroscope... repeat as above.. the left movement is the constant for no wind and changes, but is predictable with wind.

this is explained by the force of the wind blowing against a mass in motion (newton's first and second laws)


Now, take it to a bullet... essentally an elongated gyroscope....

as a spinning bullet produces NO (more accurately net-sum-zero) lift, it is a defined solid opject, moving through space.

The "spin", being (close enough in the time frame of the experiment) a constant, presents a "surface" or at least a VECTOR for the force of the air to act upon (otherwise, there would be no drift at all)

This drift, (assuming like massed objects with teh rock and gyoscope) would be LESS than either rock or gyroscope (assuming the same velocity) right?


So, a bullet fired down range, with a wind from the right moves left...

how much it moves left is a function of how much the wind's FORCE pushes against the bullet's mass and velocity.. but over TIME

since in f=ma, the a is change in acceleration, right?

so if a defined force is pushing as a constant (just to make the model simple), it would have MORE effect on a lighter bullet than a heavier one at the same velocity, right? Since the ineteria of the bullet is higher on the heavier bullet.

so, there's obviously a range of predictable results, based off the bullet's vel and mass, and the force of the wind against the bullet.

of course, a VERY fast 224 bullet would have LESS drift than a very slow .358 bullet at a given distance. example, 223 with 70gr at 3300fps (high inertia) vs a .357 shooting a 120gr at 1500fps (lower )... Yes, BC would enter into this, but not as a primary force, rather a change in the velocity factor over distance. we'll ignore that for now (as does simple ballistic physics)

So, a 22match at 1050fps drifts MORE than a 223 at 3300.. and a 400gr at 2400 moves even LESS at the same distance.

In a nutshell, wind deflection is in inverse to inertia of the bullet. High inertia, less deflection.


do you agree?

jeffe

Math, physics, and hypothetical experiments aside...I am still wondering why Vaughn’s book (which is a great book that I enjoyed) and explanation are any better or different than others.

How can you set math & physics aside when making a technical point?.
Vaughn pointed out that a stabilized spinning bullet pointed into the wind. No one else that I ever read said that, everything made sense.
The 22 standard velocity/ high velocity was an excellent example. Here you have identical bullets (bc's). The high velocity bullet at all times is faster than the standard (lower flight time). Howeverthe high velocity bullet has more wind drift because it loses more velocity (higher drag).
Take Care!

jefeosso; Your statements are all correct except for the fact that the "wind" does not blow against the side of the bullet.
(see my other posting)
I got into this flap because of the people trying to tear down Vaughn's work.
I know of no one else that has done such basic work and reported it.
Good luck!

Hawkins,
I think this is the fine point where we can disagree, and perhaps reason on. A bullet, in hypersonic air, is still a 3-d object (not a mobious).. and while hypresonic air sheers away there are still Sides for it to push against.. like mach 2 aircraft...

even if we boiled it down to the "disk" as reported by nobert (who has done amazing reseatch on penetratin (and a DR at that) of hypersonic air (he calls that a cavitation disk), then angular force from the wind would still move the bullet.. and still have it's mass to contend with.

So, to restate, even if we (for the sake of discussion) agree that wind acts on the front of a bullet to cause drift, we would both have to agree that the amount of drift can be derived from the amount of force acted on the bullets inertia, right?

Norbert has done some pretty amazing work, and perhaps someone could post a link to that.

So, here's what I believe we are agreeing to directionally...
condition.. constant 20 mph right to left wind

1: light bullet moving slow .. most effect (4)
2: heavy bullet moving slow ,, less effect (3)
3: light bullet moving fast .. less effect (2)
4: heavy bullet moving fast ... least effect (1)

or a 22lr is more affected than a 223 which is more affected than a 308 which is more affected than a 416 weatherby.. (nominal loadings)

jeffe

hawkins,

Perhaps it appeared that way to you, but I was not trying to “tear down†Vaughn’s work in any way, was only pointing out that having read many books on ballistic, I did not consider his work all that different in its conclusions, or easier to understand for the lay person, than all of the others. They all arrive at the same conclusions they just use different language to get you there.

I posted a quote from his book that agrees 100% with what jeffe just posted...which has pretty much been accepted fact in both the technical and practical aspects of shooting for a very long time.

Now that the smoke hss cleared a little I have a question...

Does gluing a sleeve over the action and barrel joint address the probelm? Was this the reason the technique was started?

quote:

Originally posted by tiggertate:
Now that the smoke hss cleared a little I have a question...

Does gluing a sleeve over the action and barrel joint address the probelm? Was this the reason the technique was started?

Makes sense, since the sleeve theory was meant to address overall stiffness, of which the barrel/receiver joint certainly plays a part.