How can I be positive that the AR rifle I plan on buying is a factory rifle and not put together by the dealer or other?  Do the upper and lower having matching serial #'s?  

No. There are no serial #'s on an upper.


To make sure, I would buy a Colt at a gunstore, and you will get the box that it came in with the serial # on the box label.

Yes that's true, but I'm looking at pre-ban.

If looking for a preban and you are not extremely knowledgeable you are taking a risk.  There are many unscrupulous dealers out there that have sold postban frankenguns as preban.  I sold all my prebans at what I believed to be price peak bought postbans and put the difference into mags and ammo.  This is I believe a smart move.  The prebans don't shoot any straighter, a compensator is a far more effective tool than a flash hider, and they shoot just as straight.

Quoted: The prebans don't shoot any straighter, a compensator is a far more effective tool than a flash hider, and they shoot just as straight.

And they are a lot cheaper you can spend the rest on ammo and practicing.....

Quoted: Quoted: The prebans don't shoot any straighter, a compensator is a far more effective tool than a flash hider, and they shoot just as straight. And they are a lot cheaper you can spend the rest on ammo and practicing.....

You guys must surely be jesting!?!?  If you need a brake to shoot a .223 then you probably weigh less than 100 lbs and are a parapalegic.  

If you ever have to use your rifle in a defensive situation, not necessarily at dark, just low light (ie dawn, dusk, etc) you will be temporarily blinded (think walking into a movie theater in the afternoon).  

And the CAR stock comes in very handy if you are shorter, or when letting your wife/GF/SO shoot your rifle. Not everyone can fit an A1 stocked AR (which is about an inch shoter than an A2) into their shoulder and still have adequate grip on the handguard.

If you don't like pre-bans, thats totally cool, just don't go around assuming that they are useless.....

Quoted: How can I be positive that the AR rifle I plan on buying is a factory rifle and not put together by the dealer or other?  Do the upper and lower having matching serial #'s?

hey doggy- only way to be sure is to get the serial number off of the lower and call the manufacturer and ask them. if the manufacturer is out of business, you can try to call the ATF with it, as they are supposed to have all the records, but good luck on getting 100% customer satisfaction from them...