doublegunshop.com - home Forums General Discussion DoubleGun BBS @ doublegunshop.com Dumb question. Cause of shot dispersion

I had wondered if this thought would turn up higher on the list of possible causes. Particularly with the recent comments about too much choke, and then on the other hand flyers out of whatever the pattern was.

I realize from the previous comments that I am going up against some generally accepted scientific information, but I believe most of what has been said is in error. The physics principles stated are generally relevant to bullets, less so to shot.

A spherical projectile does not have to slow to any predetermined speed to be dispersed by wind resistance. Because it is round it has a middle center of gravity. It is therefore impacted by the Magnus effect which is a destabilizing force on any projectile with a center of pressure ahead of the center of gravity.

Certainly, all physics pressure vectors are linked, but from a shotgun viewpoint, the only real external factor of importance is speed. Increase the speed at any choke, and you increase dispersion. Before the tech experts start tearing me apart on this, let's step away from physics and think about real world examples.

A pitcher throwing 98MPH has his ball tail up and away. It does not slow to 86MPH to tail. He can do the same thing with a whiffle ball without seams.

A muzzleloader that uses too much powder on a round ball, gets fliers and has to back off.

Turn on the garden hose at any determined degree of choke. Increase the water pressure. The water spreads out immediately from the nozzle outward. It does not travel out several feet to lose speed and be dispersed by air pressure.

If you want a single variable to increase shot dispersion from the barrel to the target, simply increase flight speed. Those little round pellets will overcome inertia and spread out.

Steve

Well, Entropy may well eventually proceed to the maximum. I find it hard to believe that matter will be able to continuously be recycled. Black Dwarf stars will develop at some point, the Universe will be full of them. Personally, I kind'a find the whole topic to be esoteric, especially since the Universe is so young, only 12.5 billion years old. Not a very big number if you think about things like the Federal Debt. In fact, I d hope I'm wrong.

Regards
Ken

VF: I follow, but remember that a cylinder shotgun charge hits the air as a clump, a choked charge as a string.

The pellets don't have individual clean air flow until they are some distance apart, thus I doubt that Magus is the initial destabilizing cause. I don't discount a contribution to dispersion, though.

Lead pellets are no longer round after the bore travel, their ballistic coefficient must vary considerably and certainly they acquire spin.

Increased dispersion with speed isn't surprising, since drag is a V2 function.


The baseball analogy doesn't play though, except for a kunckle ball. A spinning baseball or golf ball is an air pump. It accelerates a mass of air and bends the local flow exactly like a wing or a sail. The 'break' is caused by the transition from laminar flow to turbulent flow. Stand behind a driving range and watch a golf ball 'soar' after a period of ballistic flight, or watch a home run start to fly when the backspin bites in. A smooth ball won't do that, not to say that it will fly straight it just won't move in a predictable direction.

Ken, the postulated 'age' of the universe depends on the Hubble Constant which varies depending on who you read. It assumes red shift is entirely a result of recessional velocity, an assumption that increasingly is very much in doubt. Never mind that Hubble never insisted this was so, or that his original data was flawed, it just fit in so well with the preconceived notions of the originators of the 'expanding universe' theory that it gained traction.

To briefly continue, an expanding universe is not observed it is only inferred using questionable assumptions and we are then told that it does not apply on a 'local' scale. In fact, M31 is blue shifted and will collide with our galaxy in a few billion years. Galactic collisions are not uncommon, and that rather puts the lie to L-CDM. Without expansion, there is no need for a beginning or age for the universe and steady state works fine. Give gravity a finite range, even a huge one, and the need for 'dark matter' disappears. Don't laugh, many of the patches to BBT are much more absurd.

Sorry I got cranked up, but it's too cold to shoot.

Shot gun ballistics are actually pretty complicated it is amazing that they behave as predictable as they do. Your question is not a dumb one. A number or things happen when the shot leaves the barrel, 1)Higher pressure exists in the barrel then in the ambient air. This gas expands rapidly leaving the barrel pushing the shot as it goes. The shot tends to be carried by the outwardly expanding gas. 2)The shot on the outside of the load has more of an horizontal force on it then the shot in the center. 3) Some of the shot will be deformed and posses a different trajectory then the un deformed shot.4) Some of the shot will be spinning causing it to curve more.5)The fast moving shot will experience wind resistance which also causes scatter

The fact that it expands at a predictable rate is due the consistency of the quality of the shot, the powder and of the wad

No, no... by all means, continue please.

+1

You get greater dispersion than polywad!

Well, it's a shotgun BBS, so I must be brief so as not to abuse this medium, which I greatly admire and enjoy.

I'd refer you to the writings of Tom VanFlandern, Halton Arp, Geoff Burbridge, Fred Hoyle, and Hilton Ratcliffe. Do read a standard mainstream astronomy textbook also, to get the majority report.

I will leave you with the 'ultimate question' which I first saw proposed by Ratcliffe.

The question is this:

As far as we can tell, all the atoms and molecules in the universe are made of the same basic 'stuff'. The differences are very slight, and consist only of atomic weight and the energy field of the elusive 'electrons' and their well known 'quantum' character. Matter is to a very high percentage simply space.

How do the elements and resulting complex molecules 'know' how to behave? Each atom of Lead behaves exactly like any other for instance. Each molecule of nitroglycerine has exactly the same heat of decomposition. A couple protons either way, and we have vastly different physical and chemical characteristics.

Some of us find terms like 'natural properties' and statements like 'It's God's will' deeply unsatisfying.

This is why I think there is a blueprint to the universe that all matter has access to that we cannot at present detect. Sort of like a DNA code but part of the basic fabric of the cosmos.

I reject out of hand nonsense like 'there is no deep reality' or 'the universe is a hologram'. Likewise math is not reality, it's just a tool to describe reality.

Is the answer knowable? Only time will tell, but superstition and ad hoc or 'invented' physics that cannot be tested will get us nowhere.

I think we are close to being on the same page. The more I learn the less I understand.