A few weeks ago, I sorta just closed my eyes and jumped in to an AR15. I knew next to nothing about them. But now that I've learned a little more, the gun has got me a little confused. The lower says it's a 'Colt Sporter II' and is stamped .223. I found some documentation that says the Sporter II's came with A2 style sights, and a serial number list which dates the manufacture somewhere in '93. But this gun has an A1 style rear sight and an A2 style front sight. Also, the barrel is stamped 5.56.
So... is it likely that the upper isn't the original upper that came with this lower, based on the A1 style rear sight and the barrel stamping? Or are the docs I found possibly wrong? And is it ok to use the 5.56 ammo because the barrel is stamped with it, or can I only use the .223 because that's what the lower says?
So... is it likely that the upper isn't the original upper that came with this lower, based on the A1 style rear sight and the barrel stamping? Or are the docs I found possibly wrong? And is it ok to use the 5.56 ammo because the barrel is stamped with it, or can I only use the .223 because that's what the lower says?