scrambled_legs Posted January 30, 2004 Share Posted January 30, 2004 True, true... I guess a .22 shell would be different. The instructor actually had this argument with another instructor one time while camping. Finally he threw the shells into the fire and sat back down to continue roasting his marshmallow. True to his word the shells simply popped the lead out much to the dismay of his friend who was hiding behind a thick stump cursing him. Quote Link to comment Share on other sites More sharing options...
Thinker Posted January 30, 2004 Share Posted January 30, 2004 (edited) ???? must been a wacky shell. Most shells have the slug (made of soft lead) simply creased with the casing. It takes very little force to remove the slug from the casing and a whole lot of force to rip apart a brass casing. Sure, a little of the energy resulting from the combustion of the gun powder is used to separate the slug from the casing, but what happens to the rest of the energy? It either accelerates the casing, ruptures the casing, or both. edit: and all the force normally used to accelerate the slug as it travels down the length of the gun barrel is used to accelerate the casing, rip it apart, or both. Edited January 30, 2004 by Thinker Quote Link to comment Share on other sites More sharing options...
cracked Posted January 30, 2004 Share Posted January 30, 2004 Cracked: I beg to differ with you about what happens in acutality. The principle you cited is true. However, given the very LIGHT nature of the brass casing of the cited .22 caliber round compared to the relatively HEAVY lead slug, the casing (or fragment of the casing) will have a much higher velocity and move further (on the order of at least 2 magnitudes in my estimation). The lead slug will most likely not move significantly given the probability that the slug is oriented 'down' after being tossed into the fire. Being in contact with the ground further reduces the likelyhood that the slug will move. In effect, even if the slug moves as much as an inch or two inches, it essentially stays put....compared to shrapnel ripping out of the fire and causing damage. Given a larger round with thicker (and heavier) brass your assertion may be more true. It really sucks to argue with Issac Newton. Quote Link to comment Share on other sites More sharing options...
minx Posted January 30, 2004 Share Posted January 30, 2004 all i know is that i never wore a helmet to ride my bike, ski,climbing or anything else that matters. that may explain a lot but i'm still alive. Quote Link to comment Share on other sites More sharing options...
Alasdair Posted January 30, 2004 Share Posted January 30, 2004 Learning to ride a bike without training wheels... Dad - Ok I am going to hold on to the bike to hold you up and you pedel. Me - (not wearing helmet) OK I start to pedel while dad pushes... Me - Dad are you still holding on? Dad (from quite a distance away) - No I let go a while ago. I then panic and crash in to the pavement. Repeat several times, and I learned to ride a bike. I still dont wear a helmet. How the fuck do kids learn to ride bikes now when their over protective parents are too scared to let them out of the house. Quote Link to comment Share on other sites More sharing options...
scrambled_legs Posted January 30, 2004 Share Posted January 30, 2004 hahahhaa... wow I'm getting compared with Issac Newton?? I don't even remember what he was famed for... guess I just took myself out of the running. I'm just relating what my firearms instructor told me. I see how you would consider a casing to travel just as fast as the slug or blow apart. But as soon as the slug leaves the casing the energy disapates through the remaining opening. The casing obviously exploded in this case so the slug must have had some sort of extra pressure holding it in place when it blew. Quote Link to comment Share on other sites More sharing options...
scrambled_legs Posted January 30, 2004 Share Posted January 30, 2004 The reason a gun has to have such thick metal surrounding the casing is because the barrel provides no immediate scape for the energy. Bullets are actually designed so the casing can take the pressure required to release the slug. This is in case of accidental detonation. Just as a gun is designed to take the added pressure resulting from the bullet blocking the release of energy until it leaves the barrel. Obviously this safety factor isn't always there and the casing will explode in some cases. So I guess if you want to teach your kids a lesson let them play with soup instead... as was suggested Quote Link to comment Share on other sites More sharing options...
Thinker Posted January 30, 2004 Share Posted January 30, 2004 Cracked: I beg to differ with you about what happens in acutality. The principle you cited is true. However, given the very LIGHT nature of the brass casing of the cited .22 caliber round compared to the relatively HEAVY lead slug, the casing (or fragment of the casing) will have a much higher velocity and move further (on the order of at least 2 magnitudes in my estimation). The lead slug will most likely not move significantly given the probability that the slug is oriented 'down' after being tossed into the fire. Being in contact with the ground further reduces the likelyhood that the slug will move. In effect, even if the slug moves as much as an inch or two inches, it essentially stays put....compared to shrapnel ripping out of the fire and causing damage. Given a larger round with thicker (and heavier) brass your assertion may be more true. It really sucks to argue with Issac Newton. Nice try Cracked. Anybody who was awake in HS Physics realized you were refering to Newton's 3rd Law in your original post. I'm not debating whether or not the slug will move, there most certainly will be a small force exerted on the slug, but I still say it will 'stay put' (for all intents and purposes, within the boudaries of the fire). To a certain extent, it's semantics. Does moving an inch in a bonfire constitute 'staying put'? That's an open-ended question. Regarding your application of Newt's 3rd Law, please consider the fact that the casing in not elastic (in fact far from it)...that is a significant factor. In addition, force is applied outward all throughout the casing, as well as to both ends. The ratio of inside surface area of the casing compared to the surface area of one end of the slug would be a rough approximation of the ratio of the total force that would be exerted on each 'body' (casing and slug). I don't have the time or inclination to look up the densities of brass vs lead to look at the whole F=ma concept. More important that the relative densities would be the fact that the brass is thinner and easily fragments while the lead slug tends to remain a single body. The small chunks of brass can come screaming out of the fire when the gunpowder ignites. Quote Link to comment Share on other sites More sharing options...
Bronco Posted January 30, 2004 Share Posted January 30, 2004 I'm with TTT. Nothing get's you going in the morning like an exploding can of boiling corn around the campfire! HOTCHA! One time we scored one end of the can and set it with the "weakened" side down. When it blew, a geyser of steam and boiling nibblets shot the tin can 50 - 60' in the air. It was awesome! Camping with my old highschool buddies was always so relaxing. Everytime the fire crackled or popped, everybody dove for cover. Quote Link to comment Share on other sites More sharing options...
ScottP Posted January 30, 2004 Share Posted January 30, 2004 CBS- ever see that movie Siesta? Is that the one that starts out with Ellen Barkin writhing around naked in the mud at the edge of a river? Quote Link to comment Share on other sites More sharing options...
scrambled_legs Posted January 30, 2004 Share Posted January 30, 2004 As soon as the slug is removed the energy is expelled through the opening. Sure there'll be a lot of pressure applied to the inside of the casing but what can resist more pressure? Brass which would have to rip apart or lead which has to be pushed out of a pressure fit. I'm not saying that the brass won't have more force acting against it. Nor am I saying that it's not the densities of the brass vs. lead. Simply that once that force builds it wants to find the easiest escape. It would take a lot less force to push the lead out of the pressure fit than rip the brass apart. Once the slug is out, its like lighting gun powder on fire on top of a log. It simply burns up in milli-seconds. The increase in expansion caused by the powder will still cause a force against the brass but the force will mostly escape out the hole and the remaining force won't be enough to do anything. Shoulda stayed awake to learn the other laws Thinker. Quote Link to comment Share on other sites More sharing options...
To_The_Top Posted January 30, 2004 Share Posted January 30, 2004 No shit.. We blew up a lot of canned food in the day. One time a can of peas was on the campfire all of a sudden. Plunk..plink....pliiiink! run for cover, the can just missed my friends head and actually dented itself as it impailed into a tree. Another king can of beans on the fire and run like hell, just as the concussion hits, destroys the fire and we get showered by beans for what seemed like minutes..beans every where. Could be deadly, and pailed by comparison to the bullets we threw in there. Quote Link to comment Share on other sites More sharing options...
scrambled_legs Posted January 30, 2004 Share Posted January 30, 2004 hahhahahha.... beans and wiens Quote Link to comment Share on other sites More sharing options...
cracked Posted January 30, 2004 Share Posted January 30, 2004 Thinker, I'm talking conservation of momentum. If the casing of mass M1 moves to the left with speed V1, then the slug of mass M2 will move right with speed V2=M1V1/M2. Elasticity doesn't have much to do with it. It all depends on the mass ratio. Oh, and your surface area argument is severely flawed. The radial forces inside the casing cancel out unless the casing is blown apart. Assuming it is NOT blown apart, the only effective force on the casing is the pressure inside times the area of the cap. Since the pressure on the cap is the same as the pressure on the end of the slug, and since the end of the slug has the same cross-sectional area as the cap, the force on the slug is equal and opposite to the force on the casing. Quote Link to comment Share on other sites More sharing options...
marylou Posted January 30, 2004 Share Posted January 30, 2004 Siesta is my most favoritest movie of all time. It's a very strange movie with a bunch of cool actors and people in it. It's unique, and hard to explain. Can I just say see it?! Quote Link to comment Share on other sites More sharing options...
Thinker Posted January 30, 2004 Share Posted January 30, 2004 As soon as the slug is removed the energy is expelled through the opening. Sure there'll be a lot of pressure applied to the inside of the casing but what can resist more pressure? Brass which would have to rip apart or lead which has to be pushed out of a pressure fit. I'm not saying that the brass won't have more force acting against it. Nor am I saying that it's not the densities of the brass vs. lead. Simply that once that force builds it wants to find the easiest escape. It would take a lot less force to push the lead out of the pressure fit than rip the brass apart. Once the slug is out, its like lighting gun powder on fire on top of a log. It simply burns up in milli-seconds. The increase in expansion caused by the powder will still cause a force against the brass but the force will mostly escape out the hole and the remaining force won't be enough to do anything. Shoulda stayed awake to learn the other laws Thinker. My hunch is that it's a matter of TIME. If the powder burned slowly and released it's energy gradually, then the force could dissipate out the end of the casing. But, if the power burns quickly there may not be time for that to happen and more force would be exerted against the sides of the casing. Consider the extreme case where a flammable substance contained in a compressed gas cylinder ignites. The pressure plug could blow and/or the valve/regulator could blow off the top of the tank if the combustion is slow. If the combustion reaction is fast (which most are) the tank could be ripped open because there just wouldn't be enough time for the energy of the reaction to dissipate thru the end of the cylinder. Again, it's just my hunch on this point...I'm nearing the end of my desire to pursue this much more. Quote Link to comment Share on other sites More sharing options...
scrambled_legs Posted January 30, 2004 Share Posted January 30, 2004 true... but as soon as the slug is removed there is nothing for the casing mass to push against. The brass or lead will probably shoot 15'-25' (as I had said in my original post) depending on which one is pushed up against something with more mass. But neither are really dangerous unless the casing actually explodes before the slug releases. Quote Link to comment Share on other sites More sharing options...
lummox Posted January 30, 2004 Share Posted January 30, 2004 Lummox, what did your experiment indicate? my childhood play with bullets suggests strongly that it is a bad idea to throw them in a fire or to hit them with a hammer. oh yeah. here is a little charmer idea: tape a marble on the end of a shotgun shell and drop it down a stairwell. i first saw that model of fun in high school when one dropped next to me at the basement level. luckily the dumbfukers who dropped it dint know enough to put a streamer or sumpin to direct how it landed. it landed sideways but dindt explode and i learned a new trick all at once. and the really kickass firebomb is an almost empty gas can on the campfire. Quote Link to comment Share on other sites More sharing options...
sobo Posted January 30, 2004 Share Posted January 30, 2004 Thinker, I have been accused of being in several places at the same time, and for a long time I thought I had a twin out there somewhere. Reading through your list of nefarious deeds as a youngster sounds rather familiar. The twin must have been you! My brother and friends used to play "War" with each other with BB guns and the dreaded "potato gun" as our field artillery. Got shot right square in the tip of the nose at 25 feet once with the BB gun. Put an end to that game version. Managed to burn down several buildings (some on purpose, some not, although after the first few, no-one would believe me anymore when it really was an accident. Burned up a few cars while the owners were making it with their SO off in the woods somewheres Stole a few boats and went joy-riding for awhile (always returned them to the dock, tho) Brought the local constable out on a few wild goose chases after reporting dead bodies washed up on the beach. list goes on and on, ad nauseum... And yet I turned out OK, didn't I? PS: I think my dad must have whipped my bare ass with his belt every day when I was a kid, but he swears to this day it was only about once a week or so. Quote Link to comment Share on other sites More sharing options...
scrambled_legs Posted January 30, 2004 Share Posted January 30, 2004 Thinker... your Bang on... sorry. I mean gun powder is used because of its slow release of energy. It allows the somewhat fragile lead to start accelerating rather than be deformed in a massive explosion. Gasoline is actually more potent than gun powder. Same ideas surrounding combustion engines. If you get the wrong octane gas it wrecks your engine because the cylinder components will be damaged to the explosion rather than slow release of energy. It really is a slow release in terms of explosives Quote Link to comment Share on other sites More sharing options...
Thinker Posted January 30, 2004 Share Posted January 30, 2004 Thinker, I'm talking conservation of momentum. If the casing of mass M1 moves to the left with speed V1, then the slug of mass M2 will move right with speed V2=M1V1/M2. Elasticity doesn't have much to do with it. It all depends on the mass ratio. Oh, and your surface area argument is severely flawed. The radial forces inside the casing cancel out unless the casing is blown apart. Assuming it is NOT blown apart, the only effective force on the casing is the pressure inside times the area of the cap. Since the pressure on the cap is the same as the pressure on the end of the slug, and since the end of the slug has the same cross-sectional area as the cap, the force on the slug is equal and opposite to the force on the casing. My argument would stand if it were assumed that the casing WAS blown apart....which has been my whole point on this pointless thread. Quote Link to comment Share on other sites More sharing options...
cracked Posted January 30, 2004 Share Posted January 30, 2004 Thinker... your Bang on... sorry. I mean gun powder is used because of its slow release of energy. It allows the somewhat fragile lead to start accelerating rather than be deformed in a massive explosion. Gasoline is actually more potent than gun powder. Same ideas surrounding combustion engines. If you get the wrong octane gas it wrecks your engine because the cylinder components will be damaged to the explosion rather than slow release of energy. It really is a slow release in terms of explosives No, actually, if you use gas of the wrong octane you will most likely ruin your engine due to the gas exploding before the cylinder is in the proper position, commonly know as 'knocking'. That is, the piston is still decreasing the volume of the cylinder when the gas explodes, which obviously screws up the cycle. It's the timing, not the force of the combustion. Quote Link to comment Share on other sites More sharing options...
lummox Posted January 30, 2004 Share Posted January 30, 2004 the bb gun battles are classic. reminds me too dart wars. we made darts by cutting q-tips in two and cutting the flat part off of pins then shoving it into the qtip shaft. the tube from a aluminum arrow was the blowgun. fukin things went in pretty deep. we stopped playin when one kid got it in the eye. we pulled it out no problem but we were scared to play anymore. Quote Link to comment Share on other sites More sharing options...
To_The_Top Posted January 30, 2004 Share Posted January 30, 2004 Yes we had bb gun wars too. When those got taken away we resorted to rocks, which proved to be more dangerous. Blow darts? we had them too. we would take a straw, then a needle with masking tape wrapped around it then rolled in paper. They had quite a range, not that i would know though Quote Link to comment Share on other sites More sharing options...
Thinker Posted January 30, 2004 Share Posted January 30, 2004 Sobo, we stalked each other with bb guns thru haystacks that had been moved into a corner of a field near the sileage bunker, and thru cornfields. A long grazing scar underneath one of the cuz's eyes put a stop to that game. My most notorious fire involved a haystack. It was my great grand father's funeral day and we were out playing with magnifying glasses and corn husks on top of a stack...pure genius. It was a bit humiliating for us kids when the vollunteer fd had to come out and assist our grieving family. More great fun: tying our home made go carts to the hitch on a pickup and cruising down the gravel roads. going thru chutes in the river in canoes and trashing the hell out of them "skiing" with a water ski tow rope tied to a bumper on snowy roads where there wasn't a hill in sight. tipping 12' sail boats over 180 degrees in the lake just for the hell of it...and for the fun of uprighting them again. Once the mast stuck in the muddy bottom when we weren't out far enough. driving in the hay field with my cousin when neither of us were tall enough to push the gas pedal, steer, and see out the windshield all at the same time. we took turns steering and pushing the accelerator. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.