Preventing Plastic Surface Cracking

 http://www.concreteconstruction.net/concrete-construction/preventing-plastic-surface-cracking.aspx Some Midwest ready-mix producers report there have been more problems associated with plastic shrinkage in concrete this past spring. Dave Polosa, owner of Polosa Cement Contracting, Tinley Park, Ill., says that he has experienced shrinkage on his jobsites eight times so far this season. His company installs decorative concrete primarily in residential settings with most of his work involving applications of color hardeners or integrally colored concrete slabs. He notes that jobsites with southwestern exposures are the most prone to problems because that's the direction that most winds come from in his area. The ACI nomograph was first developed...

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Temperature Effects on Zero

For over three hundred years man has endeavored to find his target with the first shot from his rifle, whether it be man or beast, in conflict or at peacetime. This skill in the art of marksmanship is one of the most pondered and talked about subjects in the Military & Law Enforcement communities today. There are facts, opinions and myths covering a wide range of elements in the gap between the point at which the firing pin strikes the cartridge primer, to when the projectile strikes its target. There is no escaping the simple fact that this subject is...

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Snipers And Their Shooting Computers

 U.S. Army and Marine Corps are getting handheld ballistic computers. The 17 ounce Trimble PDA type device is loaded with Horus Vision targeting software. This enables shooters to more effectively hit targets over 2,000 meters distant. The $2,000 device is dust and waterproof, and uses rechargeable battery AA batteries. The device also has Blue Tooth and WiFi, as well as a speaker and microphone. The software handles things like weapon model, target speed and range estimation, wind speeds and many other factors. Shooters can also add, and store, data particular to their weapon, or several weapons (and recall the data for the...

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