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s2k1
07-02-2012, 7:55 PM
Working on a .308 AR build, wanted to listed what I have decided so far, and looking for suggestions on the rest.

Here's what I have:
Tactical Machining Stripped Lower
Tactical Machining Upper
Tactical Machining LPK (when it becomes available)
BCM Gunfighter Mod 4 7.62 charging handle
Troy TRX-308 free float 13.8" handrail
KNS anti-rotation pins Gen 2
Magpul MIAD grip (is there a different one for .308?)

Considering the following:
Buffer and spring from heavybuffers.com
Geissele DMR 2 stage trigger (is there a different one for .308?)
Rock River Arms RRA Operator A2 stock (just because I have one lying around, if not, then Magpul PRS for AR-10), (does .308 use a different buffer tube?)
considering Black Hole Weaponry 18" Rifle Length gas system, .750 gas block (does it use the same gas block as AR-15?)
need suggestions on BCG
AAC Blackout Flash Hider

Thoughts and suggestions welcome!

FMJBT
07-02-2012, 10:13 PM
Working on a .308 AR build, wanted to listed what I have decided so far, and looking for suggestions on the rest.

Here's what I have:
Tactical Machining Stripped Lower Good pick
Tactical Machining Upper Good pick
Tactical Machining LPK (when it becomes available) Nice, but you may be able to find a DPMS kit minus trigger for a bit cheaperBCM Gunfighter Mod 4 7.62 charging handle Good pick
Troy TRX-308 free float 13.8" handrail Better pick than the MRF 13.8.
KNS anti-rotation pins Gen 2 Good
Magpul MIAD grip (is there a different one for .308?) Good pick, same size for 5.56 and 7.62 AR's

Considering the following:
Buffer and spring from heavybuffers.com Not a bad idea, but if you go with the 18" rifle length gas system and rifle length buffer tube, you may not even need a heavy buffer. An adjustable gas block will probably go a lot further toward recoil reduction than the heavy buffer, for about the same price or less.
Geissele DMR 2 stage trigger (is there a different one for .308?) Good pick, there's a reason Geissele has so many fan boys :D
Rock River Arms RRA Operator A2 stock (just because I have one lying around, if not, then Magpul PRS for AR-10), (does .308 use a different buffer tube?) Same buffer tube for both. I'd honestly go with the RRA stock over the PRS. PRS looks cooler, and will sit better in a rear bag but the RRA stock will have a much better cheek weld.
considering Black Hole Weaponry 18" Rifle Length gas system, .750 gas block (does it use the same gas block as AR-15?) BHW would be a good pick for the barrel, also take a look at the Fulton Armory 18.5 stainless rifle gassed barrel. They are made by Criterion, which is the budget brand for Krieger. Very high quality stuff. 308 will use the same gas block as 5.56 barrels, I'd strongly suggest going with an adjustable gas block like a JP or Syrac Ordnance.
need suggestions on BCG If you can find one in stock, grab it!
AAC Blackout Flash Hider AAC makes good stuff, although I'd suggest going with a brake for a 308 rather than a flash hider.
Thoughts and suggestions welcome!

Replies above

Jwind
07-02-2012, 10:27 PM
I'm doing my build off a Quentin Defense lower, which is the lr-308 pattern. Somebody correct me if I'm wrong here but I believe TM's are based on the LR as well.

From what I can tell right now though, it seems I can fit an ar-15 LPK in, only the Bolt Catch Screw, Front Pivot Pin, Rear Take Down Pin are different. Buffer tube is the same, at least it is on my Magpul UBR, albeit the buffer is different. As for the gas block, I believe some run a 0.936 block. So I guess you should go with whichever the barrel requires.

Oh and shameless plug :D, I have a never used MIAD basic kit grip, with the Magpul wedge piece I wanna part with. Interested?

IPSICK
07-02-2012, 10:51 PM
Have you looked into the AR Gold trigger? Better concept, design, and material construction than the Geissele.

TygerAR
07-02-2012, 11:30 PM
Please do not buy from Black Hole Weaponry. People on other forums have had problems with them. Myself included. Check out other top barrels from Noveske or JP rifles. You will be much happier. The JP will come with the bolt, and both will come with the gas block.

You will only need the heavy buffer if you go with the Magpul UBR. DPMS has one also if you want to save some money. The PRS will use a rifle buffer.

Get the Bolt Carrier and spring from DPMS.

JP rifles also has a trigger if you are looking for a light weight single stage. I have both triggers, but I like the Geissele 2 stage more. Get the Geissele if you plan to shoot long range from the prone.

Yes, I am a big fan of JP, DPMS and Noveske.

As for Flash hider/brake, Take a look at the JP or Primary Weapons System. At long range a brake will be more helpful and since we're on Calguns, we can get the AAC suppressor to attach to the AAC Flash hider. So I really don't see the point of the AAC.

Just My 2 cents

s2k1
07-03-2012, 7:01 AM
Thanks all, keep them coming.

Jwind - thanks for the offer, but I already have the MIAD.

IPSIC - Haven't looked at the AR Gold, I'll have to do some research.

TygerAR - Isn't the Noveske barrel only compatable with the Armalite pattern and not the DPMS? I'll have to check out the other barrels. Would you elabarate on your flash hider/brake comment? I'm not familar with the AAC supressor to attach to the AAC Flash hider?

Thanks!

Hoop
07-03-2012, 7:10 AM
I would avoid black hole.

Brux is 450 or so for a cut rifled drop in barrel last I checked. Then there's Fulton and Rainier barrels for around 300.

Buffer tubes are the same buffer and spring are what's different. I get mine from JSESurplus. I think I may have a rifle length DPMS 308 buffer and spring laying around PM me if interested.

Triggers=Geisselle SSAE or RRA 2 stage.

FMJBT
07-03-2012, 7:37 AM
I would avoid black hole.

Brux is 450 or so for a cut rifled drop in barrel last I checked. Then there's Fulton and Rainier barrels for around 300.

Triggers=Geisselle SSAE or RRA 2 stage.

Rainiers barrels, at least the "select" line, are made by Black Hole Weaponry. I've had mixed results with the Rainier Barrels by BHW. My 5.56 barrel doesn't shoot worth a damn, groups 77 grain hand loads into about 2.5" @ 100 yards. Long range performance? Fuggedaboudit..... In contrast, their 16" 308 barrels is awsome, can't seem to miss with that one, although it does seem to run slightly over gassed. For around the same price as the Rainier/Black Hole barrels, the Fulton Armory 18.5" SS will probably be of a much more consistent quality.

+1 for RRA 2 stage triggers, hard to beat for the price.

kblack583
07-03-2012, 7:59 AM
My current 308 build is very similar to yours. I went with the below lightweight barrel from ARP. I havent tested yet but have other barrels from them and they are all tack drivers.

http://www.ar15performance.com/308_barrel

Also have an upper with the Fulton 18.5" chrome lined barrel. Its a shooter.

IPSICK
07-03-2012, 9:36 AM
...

IPSIC - Haven't looked at the AR Gold, I'll have to do some research...

Thanks!

Let me know if you have questions about the AR Gold (actually SR Gold for 308). Also if you still decide to go with Geissele, the Hi-Speed DMR or Match is probably best.

TygerAR
07-03-2012, 10:01 PM
You are right about the Noveske, My bad.

I take it you mean this AAC?
http://www.advanced-armament.com/product.aspx?pid=682

It has threads at the base to accept their suppressor. Which makes it easier to put on and remove.

A good brake will give you quicker follow up shoots at all ranges by keeping your cross hairs closer to your target. At long range, say your blast moves your muzzle 4 degrees, that's 8 MOA or 8 inches at 100 yards, 40 inches at 500 and 80 inches at 1k. If a good brake cuts that in half then it will be 4, 20 and 40 inches. With a 20x scope, those inches makes a world of difference. A flash Hider from the prone does you no good because the blast will kick up dust that will give up your position more then the flash.

A flash hider is good if your shooting on the move and avoiding someone that can shoot back. Which is why they are found on light weight carbines. After your 308 is complete, you may find that it's too heavy to run around with. Also the longer the barrel the less flash you will have.

If you what a brake/FH combo in 30 cal. I like the Battlecomp, Spikes and Primary Weapons Systems. I have the Spikes on a 300blk pistol and the PWS on a 300blk carbine. My rifles all have the JP tac brake. A pure brake will give you better recoil and muzzle control the a brake/FH combo.

My 2 cents because that's what it's worth. Do the research before spending your hard earned cash.

FMJBT
07-03-2012, 10:42 PM
You are right about the Noveske, My bad.


A good brake will give you quicker follow up shoots at all ranges by keeping your cross hairs closer to your target. At long range, say your blast moves your muzzle 4 degrees, that's 8 MOA or 8 inches at 100 yards, 40 inches at 500 and 80 inches at 1k. If a good brake cuts that in half then it will be 4, 20 and 40 inches.

Actually, it's even worse than that. 1 degree is equal to 60 minutes of angle, so being pushed 4 degrees off will equal 240 inches at 100 yards, 1200 inches at 500, and 2400 inches at 1000 yards. Typical field of view for a 14X scope at 1000 yards is about 900 inches, so the scope will be jumping over 2 times the distance of your entire field of view. I'm sure at this point it's starting to make sense how a good muzzle brake is not just nice to have for long distance shooting, but almost mandatory. With a good brake, you can actually get back on target in time to see the bullet splash against steel, you can call the hit about 2 to 3 seconds before you even hear that faint little "bink!" in the distance.

As far as flash hiders go, I really don't plan on doing much night shooting, or shooting in any scenario that I would want or need to conceal my muzzle flash from others, at least not with my own personal rifle anyway. In the event that I did end up shooting in the dark while excercising the utmost in discretion, I would probably try to utilize some sort of "solvent trap" on the end of my barrel to mitigate possible environmental contamination as well.....

Hoop
07-04-2012, 9:41 AM
Rainiers barrels, at least the "select" line, are made by Black Hole Weaponry

Yeah or another place that does similar rifling. There are a couple.

Blackhole barrels aren't bad but they've screwed up a bunch of orders lately. I know of at least 3 people who've ordered from them, waited months, only to get the wrong thing.