AR upper weight differences and application

[Sure_Shot]

I'm in the process of building a plain Jane irons only AR for toting around the woods during warmer months while I fill my deer feeders, check stands and things of that nature. My vision is to build something somewhat light weight. I planned to go with a standard carbine length upper with a fixed front sight post. But now I'm toying with the idea of a dissipator upper with a post sight. Question: how much weight can I expect to gain? Will it be that noticable? I figured with the sight radius being longer I will potentially gain in accuracy.

 

[CherryCola]

The difference in weight won't be that different. You won't notice it. What you will notice is how you feel the weight. That weight is now going to be closer to the front of the rifle instead of a little further back. This could be good or bad. If you balance it right with the right stock or if you add a rail system you could have a more balanced rifle.. but if you just use a light stock and plastic hand guards you will notice the weight being towards the front.

If you want really light then go with a free float barrel, no front sight block, and use a low profile block instead.

 

[Sure_Shot]

I plan to add a LWRC stock and Magpul K2 grip. Leaving the standard handguards on it. Putting a DD fixed rear sight.

I don't really want to FF the handguard. I have a few like that now and with the front sight being on it, I can move the guard on the end of the barrel around throwing off the sight accuracy. This being a irons gun, I want everything solid

 

[Radar363]

Or you could split the difference and get a mid-length gas system upper.
I have a carbine gas AR I built for my younger son and there is a felt difference between that and my mid length uppers but not so much that it's better or worse.

 

[mtdawg169]

I'm in the process of building a plain Jane irons only AR for toting around the woods during warmer months while I fill my deer feeders, check stands and things of that nature. My vision is to build something somewhat light weight. I planned to go with a standard carbine length upper with a fixed front sight post. But now I'm toying with the idea of a dissipator upper with a post sight. Question: how much weight can I expect to gain? Will it be that noticable? I figured with the sight radius being longer I will potentially gain in accuracy.

If you really want to shave weight, you're going to need to ditch the fixed FSB and standard hanguards. The heart of any lightweight build is a lightweight profile barrel. You'll save more weight there than anywhere else. Top it off with a low pro gas block, a lightweight modular handguard (keymod or mlok) and a set of DD fixed sights. Done.