Earlier this year, my hunting buddy and myself were consulted by the Hunting and Fishing authorities about the problem of, privately owned but escaped, red deer that were causing a lot of damage to the local agriculture and constituting a danger for the traffic. Most of the herd was food-lured back into their fence, except for 3 (the old leading hind and 2 young stags). After several months of liberty, they had regained their wild instinct and shyness for people. All other "soft" methods having failed, the local authorities decided to have the animals removed asap and in the most effective way. Being in closed season for red deer, my friend and I were duly commissioned to shoot the animals. After a few days tracking, we eventually met, on one evening. It was decided that I would shoot the old (leading) hind first, hoping to create confusion among the younger males. Distance was 200-250 meters, so I rested my elbows on my buddy's jeep to aim while my friend was taking position at the back of the car, having agreed to shoot in tandem, once the old gal was down. I let fly and the hind folded down. As expected, the younger animals were dumbfounded and roamed around, long enough to bring them down also. All well thus, until my friend cryed out with surprise and pointed at his windshield ! It showed a star shaped crack for all his height !

My rifle (a .30-06, shooting a handload of Sierra GK 165 at 884 m"/ 2900 ft"") was rested on the car hood, the muzzle being at a distance of > 20 " from the glass, so there's no way a collision could have occured. The only explanation I see is the supersonic shock caused by the bullet crossing parallel to the windshield ?!?

First time i seen it caused by a shot. Modern car windows are glued in to add support to the chassi and are sensitive to tentions in the chassi so roadbumps and temperature changes have caused some cracks.

I have shot 30/06 and other caliber rifles over pick-up hoods and leaning against door jambs of the same without breaking glass many times, but who knows? I guess the old adage of "no good deed goes unpunished" comes into play in this instance.

This happened to a rancher friend in New Mexico a few years back, while shooting his 7 RUM across the hood of his "King Ranch" Ford pickup.
The damage was considerably greater in his case.

I've seen it and done it, but with magnums with and without muzzle-brakes. If there is a chip anywhere the chances are pretty good of opening it right up. Its not the super-sonic crack, its the muzzle blast.

It is much more likely that the cracks were caused by the muzzle blast and not a supersonic wave generated by the bullet.

Muzzle blast:

Blew out the rear tail light assembly once while shooting a 50 BMG off the tailgate.

When training around vehicle's I always covered the windshield with a piece of card board.

It would not have been nice to explain broken glass during training.

Grenadier's pictures are self-explanatory, muzzle blast it is. Thanks fellows.

quote:

Originally posted by Andre Mertens:
Grenadier's pictures are self-explanatory, muzzle blast it is. Thanks fellows.

I also seen it happen by casings ejected from semi or full auto weapons.

My rifle is a Sauer 202 bolt action.

I've never seen that from just muzzle blast. I've fired many rounds of .30-06 across the hood of my trucks without damage to my windshield (I hit my antenna once but that is another story). Just the other day I cranked off a round from a short barreled .308 (a combination many people claim has excessive muzzle blast) using the across the bed toolbox on my work truck. Muzzle was 8 or 10" from the rear window and there was no damage.