Say Anything Blog

1.  I would expect the cartridge to eventually explode, and conservation of momentum might propel the bullet in one direction.  Not at 2700fps, though.  You need the firing chamber to prevent the cartridge from exploding to get that full velocity.

It’s a dumb idea no matter what, but I’m not sure it would kill you, except in a freak accident kind of thing.

2.  Recoil is pure conservation of momentum--the bullet & gas one way, the gun the other.  I would expect the very act of pulling the trigger to cause the gun to move, and the friction between the gun & the glass to cause it to move again, ensuring that the bullet wouldn’t go in the original direction.

Put differently, there is a reason that you hold the stock while firing a rifle.  It moves and kicks.

3.  The trajectories would be similar, but not identical.  The lighter bullet would leave the bullet faster, but lose more velocity due to air resistance.  Need to do a calculation including a lot of things to get the exact results.

By the way, did “Mythbusters” fire bullets straight up until one landed on their heads or something?  Personally, I’ll pass on being hit by a 180mph (about 300fps, 40% of that of 230 gr. FMJ .45 muzzle velocity) bullet.  Thanks!

(I bet a larger bullet could quite well be lethal if it fell on you, especially in the 10% chance it was going tip down when it hit...thankfully it’s not common, but it’s conceiveable)

I heard from a Doctor that he had had a patient hit a 22 cartridge and a piece of the bullet went under the skin in his head.  No big deal.

The bullet will be propelled somewhat, but not like coming out of a barrel of a gun.  I read in a gun magazine that bulk ammunition wasn’t a danger to firemen wearing their heavy coats and masks if it were to explode in their vicinity.  A cartridge in the chamber cooking off is a whole ‘nother thing.

b.  I would think that a lighter/heavier bullet and recoil depends more on the powder charge.  If you had the same powder charge it would drive both bullet weights with the same force.  The light bullet will go faster and the heavier bullet slower but the energy will be about the same.

c.  I agree with BB that the trajectories are affected by the weight of the object as well as muzzle velocity and wind resistance of the bullet. 

A faster bullet will fall as fast vertically as a slow bullet.  But the fast bullet will travel further during that same length of time.

One thing I found that was interesting is that when you shoot both uphill and downhill the trajectory is changed just about the same.  The bullet will go higher in each case in relation to your aiming point in both instances.

I saw the mythbusters show.  They were comparing the speed of a tumbling bullet at terminal velocity.  You wouldn’t want to be hit with this but it isn’t going to enter the skull.

Of course if the bullet is still traveling on its ballistic path it’s still very very dangerous.

What’s going to happen to US industry when the global warming extremists like John McCain double the price of electricity?  I would think all these factories will close and set up in countries where they aren’t scared of technology.

B. N. Mattoo (Journal of Forensic Sciences, 1984) has proposed an equation relating mass and bullet diameter that seems to do a better job. Experiments on cadavers and such have shown, for example, that a .38 caliber revolver bullet will perforate the skin and lodge in the underlying tissue at 191 feet per second and that triple-ought buckshot will do so at 213 feet per second.

My grandma told us girls that if we hated a man enough to kill him with a gun,
“you gotta aim at his pecker to hit him in the heart ... ‘cause the recoil and all ya know”
then she grinned and went about her day. She didn’t have a mean bone in her body, but she did have some priceless advice

That was interesting Woof.  I only know what I saw on mythbuster, although it doesn’t vary that much from their calculations.

What’s going to happen to US industry when the global warming extremists like John McCain double the price of electricity?  I would think all these factories will close and set up in countries where they aren’t scared of technology.

Bike Bubba

It seems to me that the rifle laying on the glass with some kind of automated non directional solenoid for instance to squeeze the trigger so that it had zero affect on the gun or glass for any motion, trying to get to neutral here, then will the bullet exit the gun pointed at the thing when before the trigger was pulled?  That’s the question.

I’m just not sure when recoil begins, as the bullet is rifling up the barrel, once the bullet leaves the muzzle, when.  It has to do with aiming science.  I think I have always tried to hold the gun too hard.  Maybe I should relax and let the gun do the work.

the AVATAR
Old Tigers are more dangerous when they believe this could be their last hunt.

From , “The League of Extraordinary Gentlemen”
Old tigers, sensing the end,
they’re at their most fierce. 
And they go down fighting.

I think about weird things.

the AVATAR
Old Tigers are more dangerous when they believe this could be their last hunt.

From , “The League of Extraordinary Gentlemen”
Old tigers, sensing the end,
they’re at their most fierce. 
And they go down fighting.

Gene, even without the trigger pull moving things around, it’s likely that the center of mass of the gun will not align perfectly with the center of the bore.  Hence, there will be a twisting as the gun is fired, and the bullet doesn’t go exactly where you thought it was pointed.

You can certainly hold a gun too hard.  I’m guilty, too.  That said, if you really want to see how accurate your guns can be, you’ll generally hold it in some kind of mechanical device or put it on sandbags that don’t get the caffeine jitters.

recoil would begin as soon as the bullet started to move.

What’s going to happen to US industry when the global warming extremists like John McCain double the price of electricity?  I would think all these factories will close and set up in countries where they aren’t scared of technology.

Recoil in the case of a handgun causes the gun to rotate around the point the gun is clasped around the grip. If you were to (don’t by the way) hold a pistol upside down, it would recoil downward.

GoB is right, it’s a simple matter of leverage.  The barrel flies up because of the position of your hand (the fulcrum).

Also, i’m pretty well convinced from personal experience that a heavier bullet has a heavier recoil.  I know nothing specifically about the load charges—on one hand it’s reasonable to assume that a cartridge with a heavier payload would require a heavier blast—but on the other hand a heavier bullet is going to be larger, leaving less space for gunpowder.

YMMV but my aching hand knows the difference between a hollowpoint and a roundnose in my 357…

[Feet make good soup!]

In an ideal situation bullet weight wouldn’t matter.  Accelerating an object with a certain amount of energy would amount to the same recoil no matter what the bullet weight.

Simple Fig Newton. 

for every action there is an equal and opposite reaction.

Throwing a ball with an equal amount of force results in an opposite force.  It doesn’t matter what the weight of the ball is if the force is the same. 

(The ball goes more faster if it’s lighter to conserve the energy.)

What’s going to happen to US industry when the global warming extremists like John McCain double the price of electricity?  I would think all these factories will close and set up in countries where they aren’t scared of technology.

Observations:

1) properly done, triggering doesn’t materially effect aim because you squeeze the hand triggering the rifle. Pulling the trigger is (depending on skill level) is either a convienient verbal abstraction or the cause of inability to group tightly :-}.  The reasons this makes such a marked difference are readily apparent.

2) The impulse (delta_F/t) doesn’t effect aim because of 2 points:
a] the 2nd law of motion, i.e.: things at rest tend to stay at rest.  There is tiny but measurable delay between the time of ignition of the propellent and the result of the energy transfer to huge mass (in relation to the slug) of the firearm from the gases pushing the slug.
b] any change in aimpoint beyond that is compensated for at the time the firearm is “sighted-in”.

3) kick causes muzzle movement (up, out) has 2 components.  1st is muzzle blast acts as a simple machine, with the folcrum at the pinion point, (not the center of mass).  This is why pistols twist in your hand, (the much shorter arm).  In this case the fulcrum is your wrist.  BTW, with a rifle the fulcrum is at the shoulder.  In both cases the point of action is at the muzzle’s tip.  2nd is precession.  The slug, (because of rifling) acts as a gyro.  This is what stablizes the slug in flight so the pointy end stays in the front.  In turn the barrel twist, while pushing against the slug to impart spin is itself pushed against by the slug, (...equal-but-opposite actions...). contrib. to the up&out of recoil.

I 1st started investigating this when I noticed that my antique shotgun pushed back&up (a 10ga., it wieghed less than 6#, so it was v.obvious), but my rifle went up&out.

Whist., in theory you are correct, but you’ve discounted the arm’s mass - its moment of inertia.  You have to overcome the tendency for the greater mass to remain at rest.  The push-back would show instantly if the firearm’s mass was 0.

- martin.musculus

Whist., in theory you are correct, but you’ve discounted the arm’s mass - its moment of inertia.  You have to overcome the tendency for the greater mass to remain at rest.  The push-back would show instantly if the firearm’s mass was 0.

If it’s mass were 0 wouldn’t it have to be moving at 186,000 miles per second?

Actually the weight of the firearm demonstrates the irrelevance of the weight of the bullet to the kick.  The same energy caused by the bullet acceleration also goes into recoil.  (Actually a bit more because the gun is also ejecting hot gas as well.)

Anyway it shows how the same kinetic energy can be held by two different masses.

What’s going to happen to US industry when the global warming extremists like John McCain double the price of electricity?  I would think all these factories will close and set up in countries where they aren’t scared of technology.

The Whistler on March 28, 2008 at 05:04 pm

No, the “wieght” of the bulet is always irrelevent.  The mass is not .

The (simplified version of the) relevant fomula is: f=ma. Where:
“f” is force; “m” is mass(of the object); and “a” is acceleration.

In this case, for our purposes a mostly accurate expression would be: m*recoil=m*a; but this simplified eq. doesn’t express the interval… the delay in ms before the impulse imparted to the firearm actually moves the firearm.  And yes, if you are developing a comprehensive equation to model the event, you’d have to account fo the mass of the ejaculated gas.

Concerning your query abt 0 mass requiring a speed of c; are you kidding? if so “ha ha ha”, if not: no. [or, rather: at what frame of reference? Be specific… ;-p ]

NB: I <u>did agree w/your underlying point, I simply pointed out that practically—as apposed to theoretically, you need to take time into consideration.

- martin.musculus

Concerning your query abt 0 mass requiring a speed of c; are you kidding? if so “ha ha ha”

Well it was a flippant comment meant to amuse myself.  But seriously, if an object has zero mass doesn’t it move at the speed of light?

This is certainly not an area I’m an expert at, but I do like to know something about the subject.

I wasn’t aware there was a time factor.  I assumed that as the bullet accelerated the firearm would accelerate to balance out the energy.

What’s going to happen to US industry when the global warming extremists like John McCain double the price of electricity?  I would think all these factories will close and set up in countries where they aren’t scared of technology.

And yes, I realize that mass is the correct term, but knowing I’m a layperson you’ll understand that the weight/mass is fairly interchangeable in terminology for me.

What’s going to happen to US industry when the global warming extremists like John McCain double the price of electricity?  I would think all these factories will close and set up in countries where they aren’t scared of technology.

Why are some of you gun lovers so incredibly stupid. Recently, the pilot of a commercial aircraft discharged his weapon accidentally in the cockpit of the plane. The pilot of the aircraft had a permit for the gun. Apparently, he did not have the brains required to use it properly. In case of a hi-jacking, he would have been a greater danger to the passengers than anyone else. I have used guns all my life. I have a great respect for them. The only way that gun will fire is if there is a round in the chamber when you pull the trigger. Everyone knows that. Then why is it that any “responsible” gun owner would shoot himself while cleaning his gun? Why would you carry a loaded rifle in a vehicle on a deer hunt? How could your dog shoot you? Before any one buys a gun they should take the “I AM NOT STUPID” test. This does not apply to gangbangers and criminals since they usually use the gun quite proficiently for its purpose: to kill other people.

With regard to rise in trajectory, it is my understanding that the sights of a rifle (M-16 at least) are configured to that there is a slight upward angle in the trajectory and the sights are adjusted (battle sight zero, or BZ) such that the strike of the round coincides exactly with the point of aim, at say, 100 yards.

Adjusting the sights thereafter is a function of adjusting for windage (left and right drift of the round) and elevation (correcting for drop in the ballistic trajectory at a given distance) .

Any-hoo, it worked for me, as I could consistently hit neck and shoulders with iron sights at the 500.

The deadliest weapon in the world is a Marine and his rifle. It is your killer instinct which must be harnessed if you expect to survive in combat. Your rifle is only a tool. It is a hard heart that kills.

If your killer instincts are not clean and strong you will hesitate at the moment of truth. You will not kill. You will become dead Marines and then you will be in a world of shit because Marines are not allowed to die without permission.

Do you maggots understand?

...for great justice

Watashiwa, perhaps the pilot would have been able to better handle his firearm if the TSA had allowed him to carry a pistol where it belongs--in a holster--instead of carrying it in a box, from whence it could be transferred to a holster upon locking the cockpit.

I don’t know exactly what happened, but reality is that when someone is forced to adhere to a cumbersome procedure, accidents happen.  Sometimes they do even when the procedures aren’t cumbersome, but that’s not the case here.

If you want “stupid,” look up “TSA” and “FAA,” which have made it difficult for pilots (most of whom carried a 1911 during their Air Force careers on every flight) to arm themselves against hijackers.

I think that “accident” is inexcusable.  I see no reason why the firearm was not left in condition 3, chamber empty.

What’s going to happen to US industry when the global warming extremists like John McCain double the price of electricity?  I would think all these factories will close and set up in countries where they aren’t scared of technology.

I dunno--how long does Achmed give you to get a round in the chamber when he crashes through the cockpit door?  Key issue here is that all of the training by the FAA/TSA did not put “keep your finger off the trigger until you’re ready to fire” into muscle memory.

That’s partially the pilot’s fault, but I would have to suggest that it’s also the training program’s fault--you emphasize too many other things, and the basics get lost.