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Scarecrow Repair
12-04-2006, 4:16 PM
A local field has a well shot up scuba tank hanging in the trees, so a friend cut the bottoms off two scuba tanks, painted them yellow, and hung them in the trees in a gully about 240 feet from my house. One is aluminum, the other steel. They make nice sounds when hit ...

How far could a bullet ricochet under ideal conditions, say if it hit the rounded top? Since we shoot down into the gully at them, I figure side hits would just end up in the dirt, and direct frontal hits would flatten or dig holes, maybe spraying fragments a short ways. I was surprised to find holes that had pretty severe angles to them, as if they had hit the sides and not glanced away. These were SS109. I didn't have any FMJ, but I figure they are more likely to break up than the SS109.

We also shot some .22LR, and I expect they are such puny things that they wouldn't go far at all.

Anybody have experience with ricochets, especially off scuba tanks?

Aluisious
12-04-2006, 4:28 PM
A local field has a well shot up scuba tank hanging in the trees, so a friend cut the bottoms off two scuba tanks, painted them yellow, and hung them in the trees in a gully about 240 feet from my house. One is aluminum, the other steel. They make nice sounds when hit ...

How far could a bullet ricochet under ideal conditions, say if it hit the rounded top? Since we shoot down into the gully at them, I figure side hits would just end up in the dirt, and direct frontal hits would flatten or dig holes, maybe spraying fragments a short ways. I was surprised to find holes that had pretty severe angles to them, as if they had hit the sides and not glanced away. These were SS109. I didn't have any FMJ, but I figure they are more likely to break up than the SS109.

We also shot some .22LR, and I expect they are such puny things that they wouldn't go far at all.

Anybody have experience with ricochets, especially off scuba tanks?
I had a fun experience with birdshot richochet when the yahoo in the lane next to me tried a headshot against a target at 5 yards and sprayed the target hanger.

Good times.

NeoWeird
12-04-2006, 4:36 PM
Ricochets can go pretty far. I forget where it was but I was watching a homevideo of a desert shoot where they were shooting their large caliber rifles at like 600-800 yards and you hear a shot and the guy filming and another guy is talking standing up behind the prone shooter and all of a sudden you see the guy talking get hit in his stomach and he flinched back and fell to the ground. He wasn't hurt, but ust heavily startled as the ricochet him square in the stomach. He was lucky they were shooting at distances like that so it had time to lose momentum.

I'm not sure how many fatal accidents there are from 180 degree ricochets, but I would not shoot at something unless I had protective glasses on. Wish I could help more on it, but being careful is the best I got.

Also, the SS109 is steel cored so it will cut through most common steels like butter. In most cases the copper and lead will strip off, but that steel penetrator will just punch through like it's a drill bit.

xenophobe
12-04-2006, 6:24 PM
I've been hit by a ricochet at 100 yards at Los Altos R&G. Not sure where it went, but I had a small red mark on my stomach.... and yeah, that hurt.

Also had some brass from a pistol hit me at a 15y range. It cut my finger where it hit.

Fjold
12-04-2006, 6:39 PM
240 feet is only 80 yards. The 22 will reach that fine. Ricochets with the 223 could travel for miles.

Stanze
12-04-2006, 6:49 PM
A former co-worker in the early 90's shot a SKS point blank into a concrete wall and almost killed himself when shrapnel seriously wounded him in the gut.

He's probably more careful nowadays with that sort of thing.;)

M. Sage
12-04-2006, 7:04 PM
Anything coming back at you probably won't have a lot of force. Ricochets are why good, tall backstops are important. A glancing bounce can keep going a long way.

Is the tank made of steel or aluminum? I think they started making them out of aluminum a while ago?

Archenemy550
12-04-2006, 7:19 PM
Only time I experienced it was shooting .40 S&W at steel targets from like 10yards, piece of the jacket came back and cut my arm.

Harbinger
12-04-2006, 7:29 PM
I've come to realize that as long as you're wearing appropriate eye protection (ballistic), ricochets (usually only fragments) won't ruin your day.

"You'll shoot your eye out, kid!" :p

Mike

Pulsar
12-04-2006, 7:32 PM
Worst ricochet I've ever experienced was when I was shooting my 1911 at a 55 gallon drum about 50 yards away. I managed to hit one of the raised ribs on the barrel and the round just dented the rib rather severely and promptly proceeded to bounce off and land 2 feet in front of me.

Aluisious
12-04-2006, 7:36 PM
Only time I experienced it was shooting .40 S&W at steel targets from like 10yards, piece of the jacket came back and cut my arm.
I once shot a target with .45 FMJ, and a big piece of the jacket was stuck in the target paper inside the bullet hole when I pulled it back in.

Still not sure exactly how that works.

ARRRR-15
12-04-2006, 8:15 PM
I learned my lesson on how bullets gather more velocity as they travel. A few years back, we were shooting at some spring steel off the rear supension of a buggy at about 100 yards. We walked up closer and noticed the .223's had gone right through it with no problems. At about 5 yards I decided to unload my last 5 rounds into it. I felt something hit my stomach and looked down to see a small hole in my shirt. I looked up and said uh oh.

Turned out to be a small 3mm size fragment. My buddy had to dig it out with a knife. Wasn't in too far.

Sure as **** never did that again.:o

cornholio1
12-04-2006, 8:26 PM
I learned my lesson on how bullets gather more velocity as they travel. A few years back, we were shooting at some spring steel off the rear supension of a buggy at about 100 yards. We walked up closer and noticed the .223's had gone right through it with no problems. At about 5 yards I decided to unload my last 5 rounds into it. I felt something hit my stomach and looked down to see a small hole in my shirt. I looked up and said uh oh.

Turned out to be a small 3mm size fragment. My buddy had to dig it out with a knife. Wasn't in too far.

Sure as **** never did that again.:o

Good thing that belly fat stopped it..haha...j/k

Satex
12-04-2006, 8:34 PM
When we used to shoot tracers at night, it would always amaze us the randomness of Ricochets. The can fly in any direction and have the weirdest trajectories. Never underestimate the potential for Ricochets. To this day, I avoid shooting at solids at close ranges.

rayra
12-04-2006, 8:37 PM
ricochets can go several hundred yards, particularly if they only glance off the target and retain much of their original velocity / direction. You really shouldn't fire deliberately on an object (likea rounded scuba tank) that could produce such a ricochet.
Used to go to Hunt Cyn / Kentucky Cyn off Angeles Crest near Pearblossom Hwy, always seemed to experience quite a few there, as the shooting areas were a couple of low arroyos that allowed shooters to be on opposite sides of them. Terrible setup when they were busy.
Enough unsafe things happening on a public range already, without adding to it by firing on curved steel or rocks etc. Anyone near me doing so shortly won't be.

James R.
12-04-2006, 8:47 PM
I learned my lesson on how bullets gather more velocity as they travel.

Ehh I think Newton would disagree ;-) Once that baby leaves the barrel it ain't gonna gather any more velocity, V = Vo + AT...

Glad to hear you weren't hurt in any event...

Regards,

James R.

cornholio1
12-04-2006, 8:55 PM
Ehh I think Newton would disagree ;-) Once that baby leaves the barrel it ain't gonna gather any more velocity, V = Vo + AT...

Glad to hear you weren't hurt in any event...

Regards,

James R.


Thats true..

ARRRR-15
12-04-2006, 9:18 PM
Good thing that belly fat stopped it..haha...j/k


I'm it helped a bit.:D

ARRRR-15
12-04-2006, 9:22 PM
Ehh I think Newton would disagree ;-) Once that baby leaves the barrel it ain't gonna gather any more velocity, V = Vo + AT...

Glad to hear you weren't hurt in any event...

Regards,

James R.


Really? How is it the rounds from 100yd went right through and the close ups didn't?:confused:

Also, don't know if it's true, but I heard if you drop a bullet from the same height of a level barrel at the moment you fire they will hit the ground at the same time.

Pulsar
12-04-2006, 10:02 PM
Really? How is it the rounds from 100yd went right through and the close ups didn't?:confused:

Also, don't know if it's true, but I heard if you drop a bullet from the same height of a level barrel at the moment you fire they will hit the ground at the same time.

Second part of your statement is true.

My guess is that it may not have even been a bullet fragment that hit you, but a piece of the buggy you were shooting at that exploded when the bullet hit it.

ARRRR-15
12-04-2006, 10:10 PM
Second part of your statement is true.

My guess is that it may not have even been a bullet fragment that hit you, but a piece of the buggy you were shooting at that exploded when the bullet hit it.


I forgot to mention that it was in fact a piece of the bullet. It had a copper color to it and the steel was similar to aluminum in color. I saved it and should have it laying around. If I find it I will try to photograph it. It's kinda small.:)

James R.
12-04-2006, 10:14 PM
Really? How is it the rounds from 100yd went right through and the close ups didn't?:confused:

Also, don't know if it's true, but I heard if you drop a bullet from the same height of a level barrel at the moment you fire they will hit the ground at the same time.

As to your first question, I dunno...doesn't make a lot of sense. Maybe because the velocity was much higher at point blank range the dynamics of how the projectile behaved when fired at a hard target were different. Typically one would expect better results up close given that KE = 1/2 MV^2 if you lose velocity, which you do over distance the kinetic energy falls off exponentially...mass is the same in both cases. So less velocity should translate into less KE and therefore less dramatic effects, but the behavior could be highly non linear as regards the impacting of the projectile with the target.

As to your last comment, yes this is true. Everything falls to the Earth at roughly ~9.8 m/s^2 an object will fall distance = 1/2 gt^2 so if the barrel is 1 meter off the ground and perfectly level the bullet will hit the ground (ignoring wind resistance which slows the falling object in the direction of the ground) in t = sqrt(2d/g) seconds later or about 0.45 seconds.

Regards,

James R.

metalhead357
12-05-2006, 12:17 AM
Well, I've been hit by two richochets; one from my buddy sitting at the same table shooting at 100 with x39, came back down range and WAPPED me on the head. No one else at the range but us. No it wasn't the shell:p Same range but me shooting a 308 and same thing happened but closer to 150 yards and Wapped me square in the forhead....kept that fragment around a while:D I can tell ya' they didn't hurt per se but scared the excriment out of places better left un named:eek: Did tag me hard enough to leave a mark for the day.......

M14Gunman
12-05-2006, 2:16 AM
As to your first question, I dunno...doesn't make a lot of sense. Maybe because the velocity was much higher at point blank range the dynamics of how the projectile behaved when fired at a hard target were different. Typically one would expect better results up close given that KE = 1/2 MV^2 if you lose velocity, which you do over distance the kinetic energy falls off exponentially...mass is the same in both cases. So less velocity should translate into less KE and therefore less dramatic effects, but the behavior could be highly non linear as regards the impacting of the projectile with the target.

As to your last comment, yes this is true. Everything falls to the Earth at roughly ~9.8 m/s^2 an object will fall distance = 1/2 gt^2 so if the barrel is 1 meter off the ground and perfectly level the bullet will hit the ground (ignoring wind resistance which slows the falling object in the direction of the ground) in t = sqrt(2d/g) seconds later or about 0.45 seconds.

Regards,

James R.

I will translate this man's physics lesson... :)

Gravity is 9.8 meters (or 32 feet) per second, per second. That is not a typo... If you place an object 32 feet off the ground and drop it, it will take exactly 1 second to hit the ground. It does not matter if it’s a bowling ball or a marble they will both take the exact same time to hit the ground.

Now, the object's speed increases exponentially. In the first second of travel it drops 32 feet. In the second second that object will drop an additional 64 feet for a total of 96 feet of travel. In the third second that object will drop an additional 96 feet for a total of 192 feet. This is of course in a vacuum.

Wind resistance and coefficient of drag come into consideration in the real world. It brings about "terminal velocity". In my physics class, the class thought terminal velocity was the speed at which a fall will kill you. NOT TRUE.. :) Terminal Velocity is different for each object. It is the fastest speed it will reach in freefall taking into consideration air density and coefficient of drag (its dimensions). (a feather will fall slower than a marble).

Take into consideration that weight has nothing to do with it. If you take two objects similar in shape and material (but not size) like a bowling ball and a marble they will both drop at equal rates until they reach terminal velocity.

This is why if you get shot with a 12 gauge 10 yards away, you die. If you get shot 50 yards away it falls down like pebbles.

xenophobe
12-05-2006, 2:28 AM
Really? How is it the rounds from 100yd went right through and the close ups didn't?:confused:

At a distance the bullet was probably not moving fast enough to fragment and powered through the metal. When you were up close it was moving so fast that the projectile fragmented upon impact. That is why.

grammaton76
12-05-2006, 3:03 AM
Now that we're talking physics... what would be necessary to, say, shoot a 55gr projectile into orbit? Just looking for muzzle velocity here... I'm aware that it would probably shatter upon hitting air if it were actually only a 55gr projectile.

I'm having thoughts of sattelites 20 years from now... a buncha little 50BMGish projectiles (yes, I know, way larger than 55gr) in low orbit, relaying telemetry to larger, more traditional sattelites to expand the overall space surveilance network.

M14Gunman
12-05-2006, 5:53 AM
Now that we're talking physics... what would be necessary to, say, shoot a 55gr projectile into orbit? Just looking for muzzle velocity here... I'm aware that it would probably shatter upon hitting air if it were actually only a 55gr projectile.

I'm having thoughts of sattelites 20 years from now... a buncha little 50BMGish projectiles (yes, I know, way larger than 55gr) in low orbit, relaying telemetry to larger, more traditional sattelites to expand the overall space surveilance network.

Obtaining space flight in this manner is not possible. There is no magic number for velocity to escape gravity because things like coefficient of drag and mass become so complex over that distance it would be different with each projectile. Changing even one slight thing about the dimensions will alter its characteristics so wildly that calculating that number would be a shot in the dark at best even if its every characteristic were apparent. Not to mention that space flight is not obtained in this manner even now due to the vehicle's mass ratio. As propellant is burnt on a rocket it becomes lighter and even though thrust does not change its velocity actually increases as it burns the propellant. Rockets then use "stages" where spent rocket boosters and their holding tanks are shed and a new stage is ignited in order to shed unnecessary weight and therefore further increasing velocity. This is not so in a bullet where as soon as the initial explosion occurs and the gas expands, the bullet increases in speed until either the gas is fully expanded or the bullet leaves the barrel. After it does so, it is slowing down exponentially. A bullet being fired is more closely compared to a shuttle's reentry procedure.

I am involved with a group of people that build model rockets. When I say model rockets I mean quarter scale replicas. They obtain heights of 15 thousand feet. There are even competitions for private citizens that can put a payload in orbit.

Very cool stuff...

hoffmang
12-05-2006, 6:47 AM
Scarecrow and all,

The other issue to consider here is whether the round remains ballistic. I'm pretty sure that the ricochets out to 100 yards and back are occurring where the return flight isn't ballistic and therefor isn't going into skin. Its also the reason why the physics seems to work fine when you shoot a bullet straight up (because it loses its ballistic trajectory at its maxima vs. firing a bullet anywhere 5 degrees plus off vertical - that bullet remains ballistic and therefor can be deadly on the way down.

You're shooting down at the scuba tank (both aluminum and steel.) As such its possible that you could get a round directly back but its both highly unlikely and if the round did return it is very unlikely to remain ballistic after hitting the tank. Wear eye protection (which I happen to know isn't an option for you) and you'll be fine.

-Gene

M14Gunman
12-05-2006, 7:24 AM
I was shooting .25 inch steel plate with my M1A one time and I noticed that it did not penetrate at an angle much more than 5 degrees of 45. I got 10 yards away and caught a copper jacket in the face.... not fun. +1 on the wear eye protection.

I also noticed that my hollow point hunting rounds penetrated easier than the FMJ surplus rounds. It did not make much sense at the time because the hollow point would mushroom on contact.... one could not argue with the holes in the metal however.

James R.
12-05-2006, 1:08 PM
Take into consideration that weight has nothing to do with it. If you take two objects similar in shape and material (but not size) like a bowling ball and a marble they will both drop at equal rates until they reach terminal velocity.

It is important to point out here for clarity that terminal velocity itself has everything to do with the mass of the object. This may not be particularly clear to some folks. Two objects having the same physical geometry but having radically different masses will achieve radically different terminal velocities. Here on Earth we relate to the masses of objects in terms of their weight in whatever units you like as a consequence of the force generated by these objects being under a constant 1g acceleration. Without gravity the concept of weight is silly and we talk about masses instead, the math is much easier this way anyhow :-)

Anyhow the whole concept of terminal velocity is based on a pretty simple concept. Gravity accelerates objects towards Earth with a force sufficient to cause a 9.8 m/s^2 increase in velocity. When an object falls through the air it encounters resistance (from the air) to this free movement which increases exponentially with respect to velocity. At some point (terminal velocity) the effective upward push of the wind resistance will be equal to the weight of the object and an equilibrium is achieved at which point you will accelerate no more. If my memory serves me for an average size and weight man this translates into about 120 miles per hour, a heavier man will of course achieve a higher terminal velocity than a lighter man etc. Same goes for projectiles, I'd much rather be hit by 223 Remington falling from the sky than say 50 BMG ;-)

Regards,

James R.

James R.
12-05-2006, 1:21 PM
I will translate this man's physics lesson... :)

Gravity is 9.8 meters (or 32 feet) per second, per second. That is not a typo... If you place an object 32 feet off the ground and drop it, it will take exactly 1 second to hit the ground. It does not matter if itís a bowling ball or a marble they will both take the exact same time to hit the ground.

I re-read your post and realized aside from what I added about terminal velocity your math is not correct above, you will not fall 32 feet if you fall for one second...

d = (gt^2)/2

That is an object will fall d (distance in meters) in t (time seconds) etc...

So to fall 9.8 meters, or roughly 32 feet it takes 1.414 seconds, not 1 second.

If you only fell for 1 second you'd fall 4.9 meters, not 9.8 meters, it's a real easy case to solve you don't even need a calculator :-)

d = (9.8 * 1^1)/2 which is just 9.8/2 = 4.9

Regards,

James

M14Gunman
12-05-2006, 4:54 PM
I re-read your post and realized aside from what I added about terminal velocity your math is not correct above, you will not fall 32 feet if you fall for one second...

d = (gt^2)/2

That is an object will fall d (distance in meters) in t (time seconds) etc...

So to fall 9.8 meters, or roughly 32 feet it takes 1.414 seconds, not 1 second.

If you only fell for 1 second you'd fall 4.9 meters, not 9.8 meters, it's a real easy case to solve you don't even need a calculator :-)

d = (9.8 * 1^1)/2 which is just 9.8/2 = 4.9

Regards,

James

I failed to take into consideration acceleration... but the point was made... :)

Aluisious
12-05-2006, 5:06 PM
Well, I've been hit by two richochets; one from my buddy sitting at the same table shooting at 100 with x39, came back down range and WAPPED me on the head. No one else at the range but us. No it wasn't the shell:p Same range but me shooting a 308 and same thing happened but closer to 150 yards and Wapped me square in the forhead....kept that fragment around a while:D I can tell ya' they didn't hurt per se but scared the excriment out of places better left un named:eek: Did tag me hard enough to leave a mark for the day.......
Do you tell people you've survived being shot in the head twice?

Aluisious
12-05-2006, 5:21 PM
I want to point out in theory one could shoot things into space, they would need to have a velocity once leaving the atmosphere of 11km/s to escape earth's gravity, though.

The real trick is figuring out how to build a projectile that won't turn into plasma within the first few feet out of the barrel at the enormous velocity that would be needed to get through the atmosphere, building a barrel that won't be destroyed during the shot, and finding a propellant that has a sufficient burn rate to propell something that fast.

Once back in the 50s, a manhole cover was blown off a nuclear test "well" of sorts with 5 times earth's escape velocity. Ultra high-speed camera's watched it happen. Basically they meant to test a nuclear failure to detonate...a test of some fuzes, to see what happened if only some of the fuzes thought to be required to detonate the nuclear component went off. Well, turned out the fuzes worked better than expected, and what was supposed to yield 1 pound of TNT ended up yielding 500 tons of TNT. At the bottom of the well they had a plug of metal which vaporized and travelled up the well at hypersonic velocity, and blew that plate into the sky at 60 km/s or so.

Probably, that manhole cover was completely destroyed after a few dozen feet of travel. The test produced a bright blue flame a few hundred feet tall, some of which was the "plug" and probably some of which was the manhole.

metalhead357
12-05-2006, 8:19 PM
Do you tell people you've survived being shot in the head twice?

LOL! You dont know the half of it! I've been shot at more times than I care to fully re-count! There's a time on opening day I got a lil' more than pepperd by some tool hunting Dove with a 3 1/2 mag shotgun and using 4 shot from less than 50 yards:eek: Yeah, that was fun- spit the leftovers from my mouth, unwedged the stuck-uns from my hat & 1 ear, blew my nose to get the pellet from up my nose, and kept finding pellets IN my jacket for the rest of the day. ((I didn't have to even get rowdy:D My friends were on him like stink on poo & the game warden was pulling them off)). Also took a shotgun blast to the front winshield that I was sitting behind; logged pellets were in the glass less than foot from where my face was. Had a tool of a friend that had a ND trying to cross a fence when we were kids and his .22 blew a hole trough my jacket as he tried to "pass" the rifle to me with the saftey off and his finger...well I hope you can figure where:p And there's more.... (And YES, I leave tools like alone after they've proven tool steel dense!!!!!)

Yep. I get grief sometimes over the moniker "metalhead" but its NOT just for the music:cool: But yes.... I've "survived" a couple shots to the head!!