Re: Armalite decisions
Although the Armalite mags are single source, they are metal, and work well. Catch a 5 pack on sale.
I like the Armalite lower parts kit for the fact that it can be ordered at a lower price without a trigger. The Armalite NM trigger might be great but I'll never know as long as Geissele keeps making theirs. You get a faster lock time with their triggers and I've never had a light primer strike in .22LR, .223, and .308 uppers.
You can buy an Armalite free float tube for 80 bucks and slap some rails on it if you need to. One on the bottom is all you need to run an Atlas bipod. 120 bucks for a .308 FF tube is cheap.
After much questioning I've found that the one item that is standard thankfully is the barrel extension. So you can use a DPMS/SR25 barrel on an Armalite with the appropriate considerations of gas port location and checking head space. Never ASSUME your head space is correct if you cannot verify it with a set of gauges.
You can even run an entire DPMS BCA in an Armalite upper or vice versa. What you ABSOLUTELY CANNOT do is run a mixture of carrier and bolt. There is a definite difference in the length of bolt between the Armalite and other pattern due to a longer tail.
When it comes to barrels I would simply look for one with a chamber cut to what appeals to you. I went with a replacement barrel cut with a .308 Obermeyer reamer. This keeps the freebore on the short side when loading to magazine length. I am not saying this is the best chamber to have, it's an old design carried over from the M1A/M14 days. It would be worth the time to call Dave Kiff and ask him if you really want to get a recommendation.
I can't afford to buy a Fulton Armory, Noveske, Rainier Arms, Krieger, etc. and compare them all. I have seen this and find it strange. If you read all the .308 semi build threads here, there seem to be two schools. They either get a cheaper barrel or it's a Krieger, which seems to be the most expensive. Lonewolf has the only build I can recall with a Noveske barrel.
I know for a fact that Brux will build you a barrel as does Lilja. I found a Rock Creek. I would not look to save money in the barrel, and then spend it on a $300 rail and a $200 PRS stock.
We haven't even touched on caliber nor what you'll use it for. Is it a bench/range queen where weight doesn't matter or are you hauling it through the woods?
If you do go .308, is this your only .308 or do you own a bolt rifle? If this is your only .308 then maybe it would make sense to go with a 20" barrel. I just would not expect it to be as accurate as a bolt rifle unless you've failed to mention that your day job is putting GAP10s together.
Other than that after doing much reading by people with much more experience, my opinion is that in .308 semis you only need a 16" barrel. It won't be optimal at 1,000 yards but how much shooting are you going to do at that distance realistically? I'm not kicking myself because I ended up with an 18", it was what was in stock and it's the same length gas system so I could use parts I already had. I would go different caliber if all my shooting was way out there.
If you decide to go with a 6 or 6.5, I would still ask about the best chamber for the bullets you want to use loaded to mag length. Based on comments from George Gardner on this forum my opinion is that GAP10s are accurate because A) they use a quality barrel, Bartlein and B) he absolutely knows what reamer he wants to use to cut the chamber. You can't buy that knowledge or expertise in an average barrel.
Plan your build exactly and don't change it mid-stream. The cheapest stock would be an A1 or A2, rifle length buffer tube. Then you can buy the cheaper buffer and spring. If you want any kind of adjustable stock, you're going to be talking to Slash about buying one of his buffers.
One last thing, misery seems to love company on the internet. Don't be surprised when you buy something that you found a few great reviews on and yours turns out to be a turd.
I have yet to see a guy that spent as much on a build and could've bought a GAP, POF, LWRC, LMT, whatever, come on to a forum and say it doesn't shoot. I have never seen anyone, on any forum, say yeah, I spent $2.5k building a rifle to my own specs and it's an honest 2 MOA rifle. If you want to see internet group denial in all it's grandeur, start talking to people that build FN FALs.
I am NOT saying that a person cannot build an accurate large AR platform. It's just not as simple as an AR15. Remember you're going to need to buy some specialized tools as well.
