Monday, September 15, 2014

Samsung SGR-A1 Robot Sentry

This sounds pretty cool and all, but either somebody is lying or got their facts wrong about the specifications. I think someone is lying (exagerating) to scare people about it capabilities which you can find here:

Capabilities:

The problem is a 5.56 MM weapon will not only not kill someone at over 2 miles it won't even go that far unless you are shooting it off the top of pikes peak to the valley below. a .223 bullet will start to tumble at 600-800 yards and will fall flat within a mile and a half. If you pointed the barrel at 37 degree angle in the air it won't go 2 miles.

9 comments:

  1. It's Samsung. The bullet will go 100 feet, and then tell you about how Apple's robot would have made you plug in by now, costs twice as much, and would only shoot 50 feet....

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  2. A 55 grn bullet out of a 1in9 or slower barrel will lose stability and go transonic in apx 600 yards, like you said. A 77grn bullet out of a 1in7 barrel can make it to 1050 to 1200 yards before having the same thing happen. Neither bullet will be particularly lethal at those distances. I don't understand why people get into the field of shooting and don't actually try to shoot things.

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  3. Gen X idiot here. What little ballistics I was taught, that I remember, said that 45 degrees was the angle for maximum distance. Googling for ballistics and 37 degrees didn't find me anything interesting.

    Point me at something to relieve my ignorance?

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  4. " I was taught, that I remember, said that 45 degrees was the angle for maximum distance."

    This is true only in a vacuum such as the moon. But in the atmosphere it is not true. I am guessing it will be around 37 degrees on earth at about sea level. I have not calculated it out but close enough. If you are still having trouble understanding use limits in your mind. Which bullet would go further in the horizontal in thick grease a bullet shot at 45 deg or a bullet shot at 0 deg? Of course the bullet shot at zero degrees will go further in the horizontal and neither will fall to the ground just stick there when it momentum is spent. You can also do the same mind experiment under water and it will help you understand why.

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  5. For a rifle bullet the range loss may be as much as a factor of 20, for an artillery shell perhaps a factor of 3 or 4 depending on its calibre. Air resistance also means the trajectory fired at an elevation of less than 45° is no longer parabolic, but elliptic - a segment of an oval curve:

    http://nigelef.tripod.com/fc_ballistics.htm

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  6. I don't understand why people get into the field of shooting and don't actually try to shoot things.

    Most people who like to shoot don't have the same opportunities we have had. I have forever had a place to shoot from any distance any weather and countless game and varmint. Most people go to a 100 yrd range and then extrapolate out in their mind and never saw that .223 bullet go through sideways that piece of tin you set up 700 yards away for example.

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  7. The local cop shop in my town has a 409 yard range. I was out on it one day shooting my new (to me) varmint master AR-15. I had zeroed at 100 and had shot a 5 shot group that were all touching. So I kept going back 100 yards at a time and shooting a new group. Every group I shot was the same, super tight.

    Then I got out to 409 yards and squeezed off my five shots. I walked down to the target. About the time I got to it a city cop showed up and started hanging his target on the station next to mine. We talked a bit. He asked what I was doing and I showed my target. The entire group fit inside half of one of the 1in squares on the target but was about 6 inches or so low of the center of the target.

    I was pleased beyond belief that I had a used gun that was shooting that good with PMC ammo. I think it showed. He told me to go and get my money back that the gun was no good. I thought he was joshing me. He was serious. He thought that there was nothing that could be done to fix a gun that was off by that much.

    The guy was a cop and didn't know about adjusting sights on a rifle.

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  8. You should have said, "6 inches low is only a minute and a half angle at 400 yards." Then set back and watched his blank expression.

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  9. I was too floored by a cop not understanding that the turret thingy on my scope could be adjusted to move the group up or down on the piece of paper. Any AR that groups that good will be able to serve its job of smoking prairie dogs. I even tied for second in a steel match with it. The person who beat me was using a 6.5x284 and was able out gun me on the long shots. He is a pretty good shooter too.

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