I have this old 80% upper and lower.

[swampfox1975]

I know it's one of colts because of the stamp above the trigger guard. The lower markings are -123 MMA 7075 The upper is marked 7075 KAE 71 where the ejection port should be. I didn't see a "c" where the c/h catch is. It is a fixed rear sight. On the lower there is no shelf like my semi's. And it is fenced around the safety. Any ideas? I was thinking maybe a 16a1?

[swampfox1975]

I think I found one similar on the retroblack rifle site. My suspicion it is a 16A1 seems to be confirmed.

[usmcvet]

If you can post a photo you will probably quickly get an answer.

[swampfox1975]

These are the photos I have of it.
http://i231.photobucket.com/albums/ee199/swampfox1975/colt%20m16/100_0662.jpg

http://i231.photobucket.com/albums/ee199/swampfox1975/colt%20m16/100_0661.jpg

http://i231.photobucket.com/albums/ee199/swampfox1975/colt%20m16/100_0658.jpg

http://i231.photobucket.com/albums/ee199/swampfox1975/colt%20m16/100_0657.jpg

http://i231.photobucket.com/albums/ee199/swampfox1975/colt%20m16/100_0656.jpg

http://i231.photobucket.com/albums/ee199/swampfox1975/colt%20m16/100_0663.jpg

[The Cat]

Looks like an A1 upper and an A2 lower. You can tell the lower's an A2 by the radius of the cuts for the front pin, and the extra beefing-up around the buffer tube area.

It'd be nice to see those completed...

[swampfox1975]

Thanks, in my mind I thought something was amiss between the two. If I were to complete the lower do you have any idea as to what requirements would have to be made for the registration?

[The Cat]

Thanks, in my mind I thought something was amiss between the two. If I were to complete the lower do you have any idea as to what requirements would have to be made for the registration?

I don't know for sure - so I'll defer to someone more educated than me about that.

Has the magwell been broached?

[swampfox1975]

yes it has all the machining except for the bolt catch, mag release catch groove, fcg holes, and takedown pin holes.