Perrazi boring

[Wonko the Sane]

Like I said before - nothing "slows".  The gas has not ceased to exert its force on the ejecta or the gun.  The rate of acceleration may slow (infinitesimally) but the fluidity of the ejecta and the relatively incremental decrease on the bore due to choke does not affect the velocity in any measurable way as cylinder and full give the same measured speeds.

You rocket analogy is not sound as well.  There is no spike in anything as the ejecta leaves the barrel as the containment vessel has ceased to exist.  the expanding gas that has been pushing on the gun all this while(and decreasing in pressure all the while) (you do understand how that works, right?) is suddenly subject to a massive drop in pressure and resulting cessation of action on the gun.  You are correct that there are minute forces in action but your reductio ad absurdum grain of rice business is just that.  You can add a multitude of infinitesimals and still not have anything but an infinitesimal.  A bigger infinitesimal? 

Here's something my first calculus professor passed along.  He called it the "for all practical purposes" tool.

And as for the headspace thing - lovely little calc with massive numbers.  I'd like to see some recoil/pressure data out of a pressure gun with increasing headspace documented.  I'd also be interested in seeing that Krieghoff data to support the swell anecdote.  Was it ever published?

I think I'm gonna do something important now.  I have some nails need trimming.

 

[timps]

Like I said this is an academic post as you were claiming that it is against the laws of physics. It’s not, simple fact. If it doesn’t slow or the force behind it doesn’t increase you can completely forget Newton’s laws of motion, putting “slow” in inverted commas doesn’t alter that fact.

I did read an article on testing that I think if memory serves me right Hamster posted on here some time ago that disagrees with you on cylinder and full choke, it did show full choke increased velocity. Regardless it doesn’t alter the science. The gas hasn’t finished expanding and even if it had gas under pressure will accelerate more once you allow the pressure to be released.  

You are completely misunderstanding Newton’s laws again regarding force, the expanding gas only moves the gun backwards on momentum change (acceleration or deceleration) of the shot and wad so it is not pushing the gun back at all once the wad reaches constant velocity in the barrel.

Once the wad stops accelerating which is way before the end of the barrel the velocity of the wad is then constant, no momentum change, so the only force that is needed to overcome is friction and pushing the air out of the way no need to overcome inertia or mass. Using your beloved F=ma  the mass is multiplied by zero as a constant velocity is zero acceleration so no force due to the mass of the object so no movement of the gun.

Although the friction of the bore is pushing back it does not move the gun or push on shoulder as its in equilibrium. The force pushing the breach backwards is cancelled out by the wad pushing the barrel forward due to friction by the same amount of force. Equal and opposite reaction type deal from Mr Newton. 

That is the first recoil pulse.

Now onto the potential energy stored as pressure, this does not move the gun until it’s released at the very end, a bottle storing 100000 psi doesn’t want to move, open a valve and it does.

The vessel does not cease to exist as the shotgun tubes don’t disappear, are you saying taking the top of a pressurised container does nothing as the vessel now ceases to exist?

The wad is impeding the flow of the gas so there is a pressure build up behind it, the gas is trying to expand faster than the wad it cannot escape quickly enough.

The gas can also be harvested to work a gas operated semi auto after it has finished being useful to adding velocity (acceleration). If this energy is enough to operate a piston to move the bolt back and eject the cartridge, then it’s not infinitesimal force. I guess the anecdotes of gas operated shot guns being kinder are Hogwarts as well.  Remember this stored potential energy does nothing until released, once released it is called the 2nd recoil.

Also if it is infinitesimal force I guess the research about 2nd recoil and muzzle brakes is all rubbish. I am not too sure why the US army and other arms manufactures fit them to certain firearms, they should have just asked you and saved fortunes on the science and testing as it is just a bigger infinitesimal. But before discounting the rocket theory just use google and you will find all the tests you need backed up with all the empirical data you need relating to muzzle brakes.

As I said, if as you first claimed it’s against Newton’s laws you are wrong,  if you now want to change the argument to whether you can feel it or not, as I have already stated I doubt you will but the science backs it up, MY WHOLE POINT.

You do have some flawed logic that cannot be used in the scientific community, there becomes a point where enough infinitesimals become a problem. I drop a grain of rice on your head from 20ft it’s not a problem, 10 tonnes of the stuff would be. Your logic it’s ok it’s a bigger infinitesimal is no good at all regarding Newtonian physics.

If you want to use physics to prove something doesn’t work and call it Hogwarts make sure the physics stands up, I only posted to say the physics stands up only to be told it doesn’t hence the debate.

Your understanding of basic high school physics is flawed,  F=ma the "a" is acceleration no acceleration no force it's not difficult.

Hope your nails are clipped I am going for a pint.

 

[ips]

some of the many many guns I have owned and or shot felt like they recoiled more than some others. I have no idea why that is and frankly my dear I don't give a dam as all this math and newtons law of thingymajig is doing my chuffing knut in. For the love of god can we stop before I turn to drink.

 

[Les53]

some of the many many guns I have owned and or shot felt like they recoiled more than some others. I have no idea why that is and frankly my dear I don't give a dam as all this math and newtons law of thingymajig is doing my chuffing knut in. For the love of god can we stop before I turn to drink.

Turn to drink? You don't usually need an excuse! :wink:

 

[Mutley]

Most guns that kick more than another of same make and model can 75% of the time be down to the stock heading up.....  or lack of.....

 

[Hamster]

Most guns that kick more than another of same make and model can 75% of the time be down to the stock heading up.....  or lack of.....

If I understand it correctly heading up refers to the fit between wood and action, interested to know how it affects recoil. 

 

[ips]

correct Hamid, I can assure you it has a dramatic effect on felt recoil. Even slightly loose stock bolt will do it. This Imo is another factor were expensive guns become worth the money, good heading.

 

[Wonko the Sane]

TIMPS - your analogies suck.  Well, maybe they blow.  Not sure which but you are clearly not envisioning the world as it is.  But that's cool.  

have a great day!!

PS - my toenail trimming came out just fine

 

[timps]

Last time I knew Newtonian mechanics is the real world as it is, it’s not up for debate. Its fine that you don’t understand physics, but calling everything Hogwarts you don’t agree with then not being able prove by any law or formula what you are saying is true just means you don’t understand classical physics not that you are right.

You keep believing in wonko physics, that’s cool too, but please don’t try and call it Newtonian as he disagrees with you.

Real glad about your toenail.

Thank you, I will have a good day as I am going for another pint.

You have a good day as well.

 

[jwpzx9r]

http://www.bbc.co.uk/news/science-environment-36773074

Why oh why don't rocket scientists realise all they need is a big shotgun

edit

wait a minute is that not a very big cartridge I see with the red band around the crimped end ? Yes exactly they know alright!

 

[timps]

Your edit is right, they already do know that all you need cylindrical combustion chamber with an opening at one end, which gas can escape governed by the lovely formula

F = qVe+(Pe-Pa)Ae

The red band is actually a Beretta skeet choke proving my point on chokes and rocket propulsion.   :ahappy:

 

[Wonko the Sane]

That just gets funnier every time I read it

 

[jwpzx9r]

This just in video footage of a recent ESP comp where the effect of a slightly over loaded  Gamebore white gold through a fairly tight choke can be quite clearly seen...George has said he will never use them again lost his eyebrows   

 

[balltrap]

That is nothing compared to the buffalo shell :wink:

 

[schmokinn]

I that not a Baikal Rekord? 

 

[jwpzx9r]

I that not a Baikal Rekord? 

My mate told me he tried them once... the guy standing next to him had to clean his gun before he fired a shot