Okay folks here is the scoop. I am the LEO who's friend made these guns for us. The place where the parts were ordered from is called Blackthorn Products. I have a very basic knowledge of the AR (recently updated and educated by some fantastic people, NED & PAT being two of them). That being said I am no where near qualified to start bashing that company. All I can speak for is my experience and we got a lot of bad stuff from them including my AR which I'll tell you about next. I would never ever order anything from Blackthorn after my friends experience. Do some Google searching for yourself (I wish he did before ordering the parts). Here are the first four Google responses that came up when I searched them. http://www.1919a4.com/forums/showthread.php?t=13297
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Know anything about Blackthorne products? - AR15 Armory.com
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http://bananafufu.blogspot.com/2010/...-they-lie.html
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http://forum.pafoa.org/general-2/623...arts-kits.html

