Bullet sparks


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RioShooter
October 17, 2008, 06:51 PM
Having just watched a movie trailer showing bullet strikes sparking on metal, I was wondering if it is possible for a bullet to create a spark when it strikes an object?

I've seen ten of thousands of bullets fired, and have yet to see one spark.

Is this just another example of Hollywood "creativity"?

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spyder1911
October 17, 2008, 06:54 PM
Well there are incendiary rounds which will light on fire upon impact but that bullets sparking is just hollywood.

moooose102
October 17, 2008, 07:03 PM
yes, the only sparks i have seen when shooting come out of the barrel, not from the bullets hitting something. now, if you were shooting steel jacketed (i know wolf ammo has some of these) bullets it could be possible. but most american ammo the bullets are either lead or copper jackets or are plated with copper. both lead, and copper are non sparking.

RyanM
October 17, 2008, 07:21 PM
I've heard of, but never witnessed, steel cored ammo striking sparks when they hit metal things.

Personally, I'm a bit doubtful. Steel cored bullets usually use mild steel, which is darn near impossible to make throw a spark.

sharkhunter2018
October 17, 2008, 07:45 PM
Bullets can spark on contact with an object.

Saw sparks while I was shooting an old oven with a Mauser. Another time, one of my freinds tried to cut the chain on the gate behind my house with his AK. A full mag and sparks from several bullets later, the chain was cut.

Both occasions were at dusk as well.

kingpin008
October 17, 2008, 07:52 PM
I shoot at an indoor range, and I've seen plenty of rounds spark as they strike the bullet trap. Does it happen every time, like the movie? Nah. But it definitely does happen.

Zipperhead
October 17, 2008, 08:03 PM
I am a fan of the historical aspects of the Air War during WWII.
Written accounts from fighter pilots on both sides mention bright flashes from bullet strikes on enemy aircraft. It may have been from the tracer rounds, but from the descriptions, it may also have been due to heat of friction from the bullets impacting the metal skin, armor or other metal components, too.

Maybe Hollywood might have a valid basis for their stuff after all? :scrutiny:

Zip

earplug
October 17, 2008, 08:19 PM
My indoor range is 25 yard with steel bullet trap. I see bullets spark all the time. Its usually a center fire rifle bullet. Steel core bullets arn't allowed and the club is real strict keeping them away. I still can't figure out how lead and copper spark when hitting steel.

Jim K
October 17, 2008, 08:35 PM
Some steel core bullets will strike sparks, but the movie spark effect is because the special effects guys don't shoot real bullets. They use small charges (like small blasting caps) wired to a battery or generator. If the target is something like a car, the holes are punched, the charges inserted, and the whole thing puttied up and painted over. The hero/villain fires, the charges explode, with sparks, the holes are revealed and the audience admires the shooting ability of the hero/villain.

Much of that kind of thing, though, has been made obsolete. Movies are now shot in digital format and the "back room boys" add muzzle flash, gunshot noise and bullet strikes to the digital master. In fact, even blank cartridges are rarely used any more; insurance costs go sky high when any operable gun is used on a set, so most of the Hollywood "hardware" is plastic.

(WWII aircraft used incendiary rounds to set fire to enemy gas tanks and other flammable materiel; tracers were inserted in belts every five rounds only for determining where the bullet stream was going.)

Jim

longdayjake
October 17, 2008, 09:20 PM
I have shot and made many many sparks in pieces of metal. They are easy to see in low light conditions and I have even seen them when shooting a rock in the dirt. You do not need steel cores to do it either. Last Saturday I was shooting my sks with some 7.62 wolf hollow points at about dusk and every shot I took at a 1/4" piece of steel was sparking. I will try to get video next time.

Owen Sparks
October 17, 2008, 09:26 PM
Lead bullets wil not spark. Copper and brass will not spark. Steel can. Some forign military surplus bullets use mild steel for jackets or steel cores that can ocaisonly spark if they hit steel but nothing like in the movies. To my knolege no American ammo maker uses steel jackets or cores. Much of the movie special effects are computer genarated now days. Any time you see pistol bullets spark when they hit a car its BS.

HB
October 17, 2008, 09:36 PM
Lead rounds can spark. Supposedly if the bullet breaks into dusk, the friction created will cause enough heat to cause the particulate lead to flask. I have never seen this happen with a bullet but have seen it with a lead airgun pellet fired into a steel trap.

HB

Bartkowski
October 17, 2008, 09:57 PM
I have seen a bb gun make sparks. Just shoot a drive way close to dark...I don't see why bullets wouldn't spark.

chris in va
October 17, 2008, 10:24 PM
I see it all the time when shooting Wolf out of my Saiga. Steel jacketed.

but nothing like in the movies. Uh huh. Actually MORE than in the movies. I'm talking a big splash of sparks everywhere.

Stevie-Ray
October 17, 2008, 11:26 PM
I've witnessed a lot of sparks in the indoor range I used to frequent. The one I go to now uses a rubber bullet trap, so no sparks there.

longdayjake
October 17, 2008, 11:31 PM
Lead bullets wil not spark. Copper and brass will not spark. Steel can. Some forign military surplus bullets use mild steel for jackets or steel cores that can ocaisonly spark if they hit steel but nothing like in the movies. To my knolege no American ammo maker uses steel jackets or cores. Much of the movie special effects are computer genarated now days. Any time you see pistol bullets spark when they hit a car its BS.

I like how despite all the people saying that they see it happen you still say that it can't. Do you ever think that maybe the steel that you shoot is what is sparking and not the lead and copper of the bullet? I don't know physics but I know that I shoot steal at nite and it sparks.

tomh1426
October 17, 2008, 11:37 PM
I shot some steel core 7.62x54 at some big rocks and it made a buncha sparks.
It helps if Its a little dark out.

bthest86
October 18, 2008, 01:00 AM
I've seen sparks also. Mostly from 22s and 7.62s hitting metal at dusk. Usually I only see them when I watch the video footage later. They are really small but still sparks none the less.

They are hard to notice at the time but easy to video tape in low light.

Owen Sparks
October 18, 2008, 01:10 AM
Before matches were invented people used steel and flint to start fires. It stands to reason that steel jacketed bullets could spark if they hit a rock. I don't see how copper, brass or lead could as they are too soft.

Dr.Carbine
October 18, 2008, 09:41 AM
At the indoor range I frequent, I have rarely seen sparks. The one time I saw sparks from nearly every bullet hitting the trap was when a guy with a FiveseveN was shooting next to me. The fast .22s were sparking like crazy. It was fun to watch.

Dutchman01
October 18, 2008, 10:59 AM
I've experienced it and can't fully explain it. I was shooting a skunk, at dusk. I was looking over the barrel and shooting as fast as I could. the skunk was actually raising it's tail at this point. I saw the bullets punching up dirt. Some of the bullets were hitting small stones in the pasture. I actually saw sparks flying.

I don't understand this as the bullets were standard federal copper clad lead bullets. The stones in this part of the country were "chert" an extremely hard stone with obsidian properties, when broken they formed razor sharp edges. I know what I saw and still don't understand it even after all these years. So, no, this may be one of those situations where hollywood isn't all that far off.

GBExpat
October 18, 2008, 11:04 AM
FYI, "chert" = flint

Eyesac
October 18, 2008, 11:32 AM
I had also never seen a bullet spark until I went out shooting at dusk... WOW! Every single round sparked when it hit the gound (beyond the target). We were shooting .223, and seriously every round sparked!

44Magnum
October 18, 2008, 04:36 PM
I also shoot at a 25 yard indoor range. My .357 and .44 magnums spark all the time when they hit the trap. I'm shooting copper jacketed bullets.

chris in va
October 18, 2008, 06:44 PM
Is it just the lead and copper melting/glowing?

Rshooter
October 18, 2008, 07:51 PM
I have seen the same thing (sparking) indoors and out with copper jacketed bullets.

230RN
October 18, 2008, 10:04 PM
Any impact generates heat.

Larger impacts generate larger amounts of heat.

A large enough impact can generate enough heat to ignite, or simply bring to a glow, the particles that break off the two substances.

Just because it is easier to use flint and steel to make sparks, and we humans use it as such for convenience' sake, doesn't mean it can't happen with other things if there is enough velocity involved.

Get a ball of ice going fast enough and make it collide with a blob of methane gas, and it will make sparks.

Lots of them, sometimes visible for millions and millions of miles.

Consider, if you will, the collision of the Shoemaker-Levy comets on Jupiter.

Ice impacting methane.

Consider also, if you will, the impact of the 820 lb copper and aluminum "bullet" we shot at comet Tempel 1. (Attached)

Or, just look up at the night sky during a meteor shower. Rocks and ice cubes hitting just the plain old air of our little blue planet.

Any impact generates heat.

Larger impacts generate larger amounts of heat.

Girodin
October 18, 2008, 10:45 PM
I have seen FMJ rounds from my 7.62x39 ak create some supprisingly (to me at least) large sparks after striking some rocks. I dont know what type of rocks they were. They were 150-200 yards away. It can definately happen.

Swede
October 19, 2008, 09:49 AM
I saw an interview with a special effects guy. He said even though you normally can't see the bullet strike it's more dramatic to see the sparks so non-shooters know where the bullets are hitting.

macadore
October 19, 2008, 11:58 AM
If I am not mistaken, bass hammers are used in environments with flammable gasses because a steel hammer striking other pieces of steel can cause sparks. It seems like a steel bullet striking another piece of steel could do the same thing.

230RN
October 19, 2008, 04:19 PM
In that case, it's because the brass particles that might get knocked off on impact do not burn in air readily, like ferrous materials, and they're softer.

The softness accounts for the fact that on impact, the energy dissipation is slowed down because of deformation. Meaning the power dissipation occurs in a longer time, resulting in lower temperatures at the collision.

Remember that power is the rate at which energy is dissipated.

With much harder steel on steel (or flint), the power dissipation is at a greater rate, since things don't get out of each others' way, resulting in higher temperatures because of the greater power dissipation rate. At some point, the broken-off particles can be heated to almost their ignition point, and sometimes the oxidation which occurs at elevated but sub-ignition temperatures can bring the particles right up to their actual ignition point.

Iron oxidation (or rusting) produces a lot of heat. You don't see it if it's just a hunk of iron sitting out, rusting, in the weather, but it does.

(I point out that when using a torch to cut steel, some welders shut off the gas after they start the cut. The pure oxygen hitting the hot workpiece makes the iron burn directly, and melt without the aid of the gas. This keeps the workpiece hot, allowing the welder to proceed with the cut with no fuel beyond the burning of the iron itself. In addition, masses of iron/ steel, like turnings and chips, can start burning on their own if they get wet. A little moisture starts a little oxidation, which raises the temperature, which increases the oxidation rate, and soon you have an iron fire. Yes, Virginia, water can start fires.)

So. Consider a brass hammer hitting Tempel 1 (see above), like the copper and aluminum "bullet" we fired at it. You can bet it will throw sparks at the velocities involved.

1911Tuner
October 19, 2008, 05:36 PM
Sparking requires heat and a goodly amount of carbon...neither of which lead or cupro-nickel have. Go hold a bullet against a grinding wheel and see if if sparks.

Iron is a pyrophoric metal. It will ignite on contact with the air. The higher the carbon content, the smaller the pieces are that break off when it strikes something, and the more it will spark.

Lead and copper aren't pyrophoric. If you're seeing sparks when your bullet impacts something, either there's something else involved, or the bullet jacket is made of mild steel...like wrought iron.

Hold wrought iron against a grinding wheel, and you'll get a small amount of erratic sparking. Use cold-rolled steel, and the sparking will increase, though still not in a spectacular way. Hold a piece of High-Speed steel to the grinder, and it'll look like the sparklers that most of us have burned ourselves with on July 4th.

230RN
October 19, 2008, 09:48 PM
The carbon "helps" in terms of initiating combustion (it's a good fuel) in the hard steel, but you have to look at it microscopically, not macroscopically.

Other materials are softer, hence have a tendency to move away and be cut off by the granules of the wheel (although softer materials tend to clog the wheel anyhow), whereas harder substances get more or less knocked off --that is, there is a higher microscopic power applied in a tiny area, resulting in higher temperatures.

Again, looking at it microscopically.

If you've ever ground cast iron, which has the highest carbon content but is pretty soft compared to hardened tool steel, you'll note that a lot fewer sparks are generated --compared to the tool steel, which throws a bright shower of sparks, as noted.

Also, the particles of the softer materials, instead of igniting like the iron in the steel, just tend to get quenched as they fly through the air. From personal experience, I can tell you that there is a small bright glow at the grinding point when you push a brass workpiece against a high speed grinding wheel. I had a 1/2 HP bench grinder which, I would brag, would eat a crowbar if you threw it at it, and I have seen this bright glow when I fed a brass rod against the wheel. (I was trying to dress a rather rough end of the rod. Yes, it loaded the wheel, but I kept a star wheel wheel dresser handy. I like my carborundum granules sharp.)

By the way, I think they use bronze hammers in mines and other flammable-gas or combustible powder areas rather than brass, simply because it's harder than brass.

You really have to look at things microscopically sometimes. My personal feeling is that the use of oil on sharpening stones is more to keep that microscopic edge cool while sharpening than to "float" particles away.

And if you don't believe that high temperatures can be generated in tiny areas, just try running your thumbnail briskly against your pants leg. You may burn yourself.

That's the old-fashioned way of lighting matches... if you remember that far back.

And hitting Tempel 1 with that brass or bronze hammer would have thrown sparks.

Even a lead hammer would have.

But that's at 10 kilometers per second.

About 22,000 miles per hour.

Macroscopically speaking.

1858rem
October 19, 2008, 10:04 PM
totally agree with 230RN:cool:

1911Tuner
October 19, 2008, 10:06 PM
From personal experience, I can tell you that there is a small bright glow at the grinding point when you agressively force a brass workpice against a high speed grinding wheel.

Yup. Anything will glow if it gets hot enough. Even a rock.

Press cast iron against a wheel aggressively, and it'll shower sparks, too.

Any metal that is a pyrophoric metal that will ignite spontaneously on contact with air will spark when fractured. The amount depends on how hard it is to fracture and how much heat is applied, and how quickly it's applied.
Finer grained steels spark more agressively than coarse-grained steels...like cast iron.

Anyway...a copper jacketed or antimonial lead bullet emitting even a small a shower of sparks on impact with a rock? I don't think so...not unless there are other materials involved.

1911Tuner
October 19, 2008, 10:19 PM
Maybe this'll help. My metallurgy classes were long, long ago in a galaxy far, far away.

http://www.survivaltopics.com/survival/flint-and-steel-what-causes-the-sparks/

lonegunman
October 19, 2008, 10:25 PM
Some of the eastern european and russian ammo is actually guilded metal or steel jacketed and copper washed. When it hits a metal backstop or something hard it sparks nicely.

If you are shooting some other types of surplus, it may be unmarked tracer, incendiary or someother type of ammo that will spark.


Plenty of surplus is mild steel cored. It is not AP nor is it considered AP because it would normally penatrate a bullet proof vest with a lead core.

The cores get amazingly hot, if you find them after impact, some are blue from heat. There is nothing amazing or galactic in nature occuring.

hso
October 19, 2008, 11:57 PM
I've seen it mostly from carbine and rifle rounds impacting metal or concrete/stone.

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