This is AR #1
As pictured with a full magazine it weighs 6.5 pounds.
I did not intend to build a lightweight gun. It just turned out that way when I bought the CavAid lower.
CavAid MKII lower
9MM RRA buffer
Upper is CMMG govt profile 1/7
And the previously mentioned Clark Custom free-float tube.
It shoots real soft and handles like very well.
Now if a guy cut the barrel down to 18" and re-profiled the front of the gun to a lightweight profile, you would lose a few more ounces and have the best of both worlds.
A very light 18" gun that shoots like a rifle but handles like a carbine. I think it would be easy to get the weight at or under six pounds of a 10 or 20 round mag is used.
There is a thread in the archives where a guy chopped the CavArms stock down. That could be done to get the right LOP and shave even more weight.
My .02 cents adjusted for inflation
ZM