Posted on 01/03/2020 8:38:00 PM PST by Tolerance Sucks Rocks
Or a C-sized battery suspended by fishing line from an Interstate overpass (known to happen in Argentina to stop cars for robbery).
What can happen when they move up from pellet guns.
Highway sniper scene from the film “Targets” 1968.
https://www.youtube.com/watch?v=3DnVkK-6sPg
You too?!
I have done it twice!
I broke my back door and a window in two separate weed eater/ pebble incidents.
Living in California in the 2000’s, I had side windows shot out two separate times. The first time the cops couldn’t find who did it (all I had was the place on the street where it happened and it was by a hillside with several dozen homes). The second time I told the cops where it happened, they sent a patrol car and the kids didn’t take the time to look at the whole car as it came down the street. They shot out a police car window. Air soft pellets both times. The kids got caught and the parents had to buy me a new passenger side window.
Actually, the front windshield is laminated. Two thin pieces of glass with a layer of clear flexible plastic (polyvinylbuterate) sandwiched in between. When not constrained, laminated glass is very brittle and breaks rather easily.
It’s used in the front windshield as a structural member of the cockpit and is constrained by the polyurethane adhesive not only for structural rigidity but also occupant safety to keep occupant in the cabin during a crash.
Because of the easier breakage and the relative inability to cleanly finish the edges (which are weaker) heat tempered glass is used in the sides. Tempered glass is amazingly strong when hit in the field, but very weak on the edges.
(I’ve hit tempered glass with a sledge hammer and not broken it. (the sledge is a hard but large diameter hit. A pellet is small enough to put very directed energy to cause the fracture.)
The nice this about tempered glass is that when it shatters, by design, it breaks into millions of small and safe pieces. The only real injuries are small pinprick type. It doesn’t shatter as much as it imploded and drops harmlessly to the ground.
I think for rear windows, they use tempered because some rear windows are very complex designs and it’s likely easier to manufacture plus maybe the shock of closing rear hatches might be better with tempered.
So, it’s not a surprise that there haven’t been any injuries. You sort of have to work at it to hurt yourself breaking tempered glass
BBs do not have the mass or velocity of a pellet.
so, on my pump air rifle, with say 10 pumps, a pellet has greater velocity than a BB
I understand the mass but given the same force of air pressure, it seems the heavier pellet would have less velocity
Where V^2 = M/F
Add or subtract the the velocity of the target to get the actual velocity.
Pellets also deform very easily.
Dead of winter, heat on in the cars. Tempered glass is funny stuff under those conditions.
Your equation is rather messed up:
F = m * a; a = F / m (acceleration)
V = a * t; V = F/m * t
I have had BBs guns and pellet rifles. The pellet rifle had considerably more destructive/penetration power. On the other hand, I've never owned a BB gun that could be pumped up like a pellet rifle. I have owned CO2 versions of each; and, pellets always seemed more effective to me.
I searched the Internet for air rifle ballistics. Detailed information seems to be available only for pellets. Maybe BBs are not considered worth the effort of making the measurements, perhaps due to their inherent lack of accuracy.
Indeed!
...while BBs bounce off, retaining most of their kinetic energy.
They found rings in the car metal. Should be enough energy to initiate a tiny fracture in tempered glass.
As a kid, I was once quite confident that BBs from my shot-out pistol would be harmless after bouncing off the street 60 feet away, so was not worried about the neighbor’s window about 100 feet away. My confidence was ill-founded.
Dings.
yup
My Crossman air rifle will fire both pellets and BB’s.
As a practical matter, I shoot only stray cats that hunt birds at my feeders and squirrels that get out of hand. I shoot BB’s at what I think of as half power. The intent is to discourage rather than harm or kill.
However, the info you provided will be useful should the need arise. When pumped ten times the range and accuracy are quite effective.
They hurtle 70 mph down the road partly because they’re REQUIRED to strap their children into special seats, making the adults think that it’s safer to hurtle 70 mph down the road.
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