AR Lower caliber markings

[Guest Khitan]

I decided to build an AR and during my search for a good lower I found that they are marked with caliber. Some say 5.56 some say Multi some say 5.56/223. My question is about legal issues

I know that if a lower is marked Pistol then it can only be used to build an AR pistol. Does the same hold true for caliber. If I have a 5.56 marked lower can I legally put a .308 upper on it?

[Spiffy]

That is just so people can use the same lower for other calibers. It has no legal binding of which I am aware.

Like using different uppers on the same lower. You can't use a .308 on a .233/5.56 lower. Any of the others that do not require modifcation of the lower (magwell, LPK,ect) can be used.

Edited August 3, 2009 by Spiffy

[nightrunner]

the .308 fits an AR-10 lower, not a AR-15 lower.

but it doesnt matter what upper you put on your lower whether it is marked 5.56 or multi or even something else. pistol and rifle cant be changed but caliber doesnt matter, unless you go and register a SBR lower and then its up to the ATF agent that processes your form what you have on it.

[Guest Khitan]

Thanks for the help guys!!