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I haven't read this whole thread, so perhaps someone else has expressed this thought, but my opinion is that swinging the shotgun barrel will not result in any change in the shape of the pattern or to the column of shot as it moves through the air.

There are 3 reasons for this; the length of the shot column as it exits the muzzle and the velocity of the shot charge and the velocity of the muzzle as it moves in a direction more or less perpendicular to the direction of fire.

The shot charge takes about 1/14000th if a second to clear the muzzle once it gets there while the barrel, which is moving at perhaps 10 mph would move only 12/1000 of an inch while this was occuring.

It ought to be pretty clear that there is no "spraying" effect--as there would be in the case of a garden hose. Everything happens much too fast for that.

I think,,,,,, 8)
 
I don't claim to understand the physics here... you guys seem more knowledgable than I am.

I can however, relate an experiment we conducted last summer. We took a roll of butcher paper, and strung it from the skeet low house and the center stake. Using a rabbit machine next to the low house, we shot several rabbit targets and recorded the results of our shots - which were taken at about 24 yards. Our patterns were roughly 25% longer than they were high - ie: an oblong pattern that we concluded (perhaps wrongly) must have been due to gun speed. If it's not due to gun speed, I'd love it if someone could explain it for me...
 
drsfmd said:
Our patterns were roughly 25% longer than they were high - ie: an oblong pattern that we concluded (perhaps wrongly) must have been due to gun speed.
One thing: Did you do a control for your experiment, i.e. did you fire from the same distance at the same paper with a stationary gun? If so, what were those patterns like?

Also, at the time the trigger was pulled, was the gun barrel at a perfect right angle to the plane of the paper? Logically, any side-to-side deviation from 90 degrees would give you a pattern that is wider than it is tall, and any up-and-down deviation would have the opposite effect. Think of it this way: Unless the gun barrel is at right angles to the target, the rear of the shot string will hit the paper in a slightly different place than the front of the shot string, leaving a wider pattern.
 
Since the acceleration of gravity does not impart a constant velocity, the shot string is not traveling a straight line, but curving downward in a parabolic manner by 32ft/ sec sq. less the vertical component of velocity (if it is not being shot level to the earth). I think the gun swing imparts a vector which is defined by a straight line. So the shot string is curving downward while traveling straight in the left to right plane. The garden hose swing is the same thing, slowed down a bit.
 
Given: A stationary gun is fired when positioned ninety degrees to a moving pattern board 6 feet high and 20 feet wide traveling at forth miles per hour forty yards in front of the muzzle. This is similar to crossing duck shots. What shape will the pattern be?

Is a duck flying at 40mph and crossing in front of the gun, more or less likely to be killed (assuming the barrel is pointed in the right direction when the shot is fired) than a duck that stopped, mid flight, for a few milliseconds because she suspected she'd left the iron plugged in and may have to go back and unplug it?

Although it sounds absurd, the reasoning involves a valid concept.

http://stockfitting.virtualave.net
 
The gun was approximately 90 degrees from the paper when fired... obviously, the gun was moving, so I can't say for absolute sure... but they weren't shot at an extreme angle.

We took a single patterning shot with the gun stationary - just to make sure that everything looked "normal" - which it did.
 
Discussion starter · #51 ·
To keep beating this dying horse,,,,,

I've thought about this for a few days, and asked a few of my friends, getting varied and conflicting answers, and it dawned on me:

1. The B-17's I used for an example in a previous post were all full of bombs. They flew about 200 miles per hour East towards Berlin (or Dresden, or take your pick). When they dropped their bombs, the bombadier looked AHEAD of the plane, though his complicated Norden bomb sight, at where he wanted the bombs to strike, and when those bombs left the planes they initially "carried" their 200 mile per hour "forward" (Eastern) direction with them as they curved toward the earth in a parabola. They picked up speed as they fell, and they no doubt slowed down in their Eastern motion and lost some of that 200 miles per hour forward movement they "carried" from the plane as they fell. From above the B-17, an observer would have seen the B-17 fly on East and the bombs "arc" down, and the "arc" would have taken the bombs further East than where they were dropped from the plane, true, but the "curve" of the "arc" or "parabola" the observer would have seen would have been "bending" in the opposite direction, back to the West. I ain't no physicist, but I'm convinced this is true.

2. If dropping bombs fall in an arc downward, and we all know they would, why in the world wouldn't bullets shot straight out at 90 degrees from the B-17 not do the SAME thing,,,exhibit an "arc" back to the West, as they slowed down from the air resistance (they would also be falling from gravity, and slowing down instead of picking up speed as a falling bomb would). To prove the point, if the belly turret gunner shot his bullets straight down at a ME-109, they would curve back West, wouldn't they?

The more I think about this, I'm convinced that the "curve" we see at night from the shot string is that "arc" caused by the charge slowing down and loosing it's forward motion, just like the bombs falling from a bomber would have and "arc". I have no idea how fast a gun muzzle is when a skeet shooter is swinging it quickly. Whatever it is, it's enough to impart THAT much forward motion to the shot charge, which will show an arc as it slows down. It's not very much of an "arc", but I can see it and so can my friends. Nobody sees it "arcing" IN THE DIRECTION OF THE SWING. A few say they see it "scattering" or "widening" the pattern, but I don't.

As to the "widening" or "scattering", I agree that the shot is all contained in the shot cup, and is only at the muzzle's end for the twinkeling of a millisecond (scientific term there :lol: ) I don't think it could "scatter" from that. But, we all know that shot charges have flyers, those flattened pellets that don't fly straight and are flattened from forcing cones, barrel walls, and violence of sudden acceleration. The plastic shot cup helps that, but we still get flyers. Flyers are less areodynamic than the good round pellets in the main charge, right? They slow down quicker, right? So why wouldn't the flyers tend to "scatter" to the OPPOSITE direction of the gun swing, as compared to the main charge? The more I think about it, the fact that flyers would slow down quicker than the main charge would actually make them arrive at the target area later, and to the opposite direction of the swing, therefore making the pattern itself slightly wider. It's not the end of the barrel that "scatters" the pellets, but the forward speed imparted by the swinging barrel, with the flyers slowing down quicker.

Or maybe I shoulda took physics back in High School :D
 
SuperXOne said:
Or maybe I shoulda took physics back in High School :D
It's never too late to take a physics (or Calculus) course you know.... :idea:

Since this thread started, I too have been thinking about it, and even started drawing it all out and working up all of the calculations. If yer interested, and when I get it done, I can PM it to you. The assumptions for my modeling is 30-inch barrel moving at a constant rate (zero acceleration, but fixed velocity) of 20 Mph, and a wad/shot column traveling at 900 Mph out of the muzzle. The basic model looks about the same as if you shot a stationary shotgun in a 20 Mph cross wind, but I want to zero in on what is happening to the wad colum in the short interval that it is exiting the muzzle.

MM3
 
Good morning everyone: Well I'd have to say maybe! LOL

I use to shoot practice rounds of skeet with a friend, who would "jerk" his .410 as he pulled the trigger. He believed that he could "bend" the shot string. I couldn't argue with him simply because he consistantly shot 24 or 25 out of 25.

I will say using a load with a cupped wad, I don't think this can be done. But using a load with a fiber wad possibly, since the shot is free to move down the barrel, with nothing, restraining it. Then again it just might be the fact that a cupped wad shoots tighter than a load using a fiber wad.

I do know after years of waterfowling, a 30MPH wind can defineatly "bend" your shot string! LOL

Regards to all

Dave
 
only winchesters said:
I do know after years of waterfowling, a 30MPH wind can defineatly "bend" your shot string! LOL
Dave
Well there you go then... A gun moving at 30 Mph in one direction shot into stationary air molecules is basicaly the same as a stationary gun shot into air molecules that are moving at 30 Mph in the other direction.

MM3
 
Mokeman3 said:
only winchesters said:
I do know after years of waterfowling, a 30MPH wind can defineatly "bend" your shot string! LOL
Dave
Well there you go then... A gun moving at 30 Mph in one direction shot into stationary air molecules is basicaly the same as a stationary gun shot into air molecules that are moving at 30 Mph in the other direction.

MM3
What planet is this physics prominent on????? :?: :?: :?:

Calculating the lateral velocity of a swing gun barrel at a skeet target from station 4 comes out to something like 2MPH, not 20MPH. Even if it were 20MPH, the shot is leaving tha barrel at something like 820MPH! Any force or lateral velocity imparted on the shot column is negligable!

To further complicate matters, this lateral velocity (a force on the shot column, actually) is actually the result of centripital force. And once the shot leaves the barrel, it is no longer applied, thus the shot will fly straight from the moment it leaves the barrel. It is not the same as a bullet leaving the barrel of a gun fired in a B17 or a bomb being released from the same plane. Both of those are the result of lateral velocity, not centripital force.

Frank
 
Hello everyone: Are you still laughing Frank?

Mokeman: Big difference in "trying to jerk" your barrel as you shoot to try to get the shot COLUMB to spread left to right or right to left, than having a 30MPH wind blow your 8-12 ft. shot string at 35-45 yards.

Again, when one considers that the shot columb is basically encased in the plastic cup wad, even after it leaves the muzzle for X number of feet, your not going to spread the shot.

Using a fiber wad in lieu of a cupped wad, the timing would have to be so close, your talking probably mili-seconds, as some of the shot has left, and some remaining in the barrel. Just don't see how it can be done with any level of consistancy, if at all.

Regards Dave
 
UltraMag said:
This thread is still going?
Nope, I'm out... (folks missing my point was my cue)

UltraMag said:
Hopefully the spring warmup
will put a stop to these idle ramblings :wink: 8)
Little dissapointed with your choice of words here (idle ramblings?), but I get your drift - I'll take the physics, and ballistics calculations offline.

Thanks,
MM3
 
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