Looking for advice on a first build

[Cakey]

This will be long but if your like me and reading this on the can, then your in a comfortable spot. I'm attempting to build my first AR 308. I've shot them but never owned one. I own rifles, pistols and revolvers. I reload as well. I enjoy reloading almost as much as shooting. I want to build a rifle that will primarily fill two roles, hunting and target shooting. I want to design a rifle that will have as gentile a recoil impules as I can build for fast follow up and pure shooting enjoyment. I am not recoil averse but I see no need to have any more than necessary. My budget isnt unlimited but I believe you get what you pay for. If I can pay less for something that serves the same role then I will but I wont bastardized my build and end up with something I dont enjoy. So this is the parts list I have come up with so far. Please let me know if you think this will fit my goals or I need to adjust. I am looking for constructive criticism, you can be critical just dont be a dick. 

 

- Areo Precision M5E1 builders kit with 15" M-LOK handgaurd

- Aero Precision rifle length stainless steel gas tube

- Aero Precision AR 308 ambidextrous charging handle 

- Aero Precision M5 lower parts kit minus FCG and pistol grip

- RCA titanium complete BCG

- AR10R-XH 308 rifle buffer from heavybuffers.com

- Luth-AR MBA-3 carbine buttstock

- Geissele Hi-Speed national match trigger set.

- Magpul MIAD GEN 1.1 grip type 1

- Superlative Arms .750" adjustable gas block

- X-Caliber barrell, 20" fluted. I'd like a 1 in 9 twist but not sure yet. 1 in 9 is only offered in 6 grove not 5r. Looking for advice on how much this will mater or if anyone else done a 1 in 9 5r. 

- Oden Works ATLAT compensator 

- Oden Works Ambidextrous modular safety

Estimated cost $2,376.10 not including shipping or the fact I plan on buying as much as possible during sale opportunities

Estimated weight 8.2 lbs without optics. 

[jtallen83]

Two items seem to contradict each other, a light weight titanium BCG and then a heavy buffer, what’s the rationale on that?

[Sisco]

The Luth stock is good, but check with them about mixing a rifle gas and buffer system with a carbine length stock. Need to make sure the measurements match. I use the MBA -1 rifle stock with my rifle length gas system on my AR10 T Carbine. Also Heavy buffers are excellent, but if you read some of the older threads, buying your complete buffer assembly from Armalite will save some money and has an outstanding track record. And it will fit in the MBA-1 stock, as that is what I have.

Edited February 18, 2020 by Sisco

[Cakey]

44 minutes ago, jtallen83 said:

Two items seem to contradict each other, a light weight titanium BCG and then a heavy buffer, what’s the rationale on that?

As I understand it (which isnt saying much) is that recoil mitigation comes down to slowing down and or lightning the mass of the reciprocating mass inside the rifle. The idea with the light weight BCG is to lighten the mass and the heavy buffer is to really slow it down. Cycle time dosnt need to be fast for me. Do I have the concept wrong? I dont have a great understanding of buffer function I guess. Im currently reading about it on the forum.

[Cakey]

8 minutes ago, Sisco said:

The Luth stock is good, but check with them about mixing a rifle gas and buffer system with a carbine length stock. Need to make sure the measurements match. I use the MBA -1 rifle stock with my rifle length gas system on my AR10 T Carbine.

Thank you I will check in on this. Buffer tubes and lengths is probably my least researched area. I'm rapidly finding out I need to fix that. 

[jtallen83]

1 hour ago, Cakey said:

The idea with the light weight BCG is to lighten the mass and the heavy buffer is to really slow it down.

They essentially become one reciprocating mass so taking weight off one and adding weight to the other negates the effects, also negates a good deal from your bank account. Lightweight BCG's are really only a plus when building race guns. When you lighten the reciprocating mass you do ease the recoil but can pay a price on the reliability side. For a recoil system you cannot go wrong with get the Armalite kit linked here, both in reliability and in price it is the gold standard for the platform. It uses the AR-15 H-3 buffer so if you want to start playing with lowering mass you have lots of different weight buffers to choose from.

https://www.armalite.com/product/ar10rekit01-6-position-receiver-extension-kit/

I have tried the Superlative gas block on a 16 inch rifle gas 308 and on the bypass side, the advantage to the brand, it will not allow enough gas to bypass to make much difference, it will not adjust far enough to stop function so cannot be set per the factory instructions. It only worked on the restrictive side so you are adding an extra complication for no real advantage over other basic restrictive type adjustable blocks. Overall there isn't that much advantage to an adjustable gas block unless you are running a suppressor. You can ease the recoil some by turning it down but again the more you turn it down the more you lose on the reliability side. I think you may be better served in your recoil and muzzle rise goals with a good muzzle brake/compensator or a suppressor.

I have not built a totally low mass rifle in the large platform but have in the AR-15, low mass BCG, a reduced power recoil spring, and a buffer with all the weights removed. It is a very soft shooting rifle and stays on target when the bolt comes home. A great range toy for the wife and kids but NOT the rifle I would use for hunting or home defense due to the chance of malfunctions being greatly increased.

[shooterrex]

Less mass moving back and forth = less recoil. Light weight BCG + Light weight buffer and adjustable gas block.

[98Z5V]

11 hours ago, Cakey said:

- RCA titanium complete BCG

- AR10R-XH 308 rifle buffer from heavybuffers.com

 

- X-Caliber barrell, 20" fluted. I'd like a 1 in 9 twist but not sure yet. 1 in 9 is only offered in 6 grove not 5r. Looking for advice on how much this will mater or if anyone else done a 1 in 9 5r.

The buffer and BCG are a weird combination, as mentioned previously.  That's just spending money for no real gain or benefit.  Weight is what softens the recoil of a .308 Win round, as well as spring pressure.  I finished one not long ago - full mass Toolcraft BCG, Armalite AR-10 Rifle recoil system (EA1095 spring and 5.4oz 5.200" .308 Rifle Buffer).  After that, I added another 4oz into the back of the BCG body.  THAT is a soft shooter, scope stays on target during shots at long distances...

Instead of that barrel, I'd buy this one and be done.  It's gonna shoot very, very accurately, too. 

https://www.ballisticadvantage.com/20-inch-308-fluted-rifle-ss-premium-barrel.html

If not that barrel, or I was in a pinch and it was out of stock, I wouldn't hesitatea second to buy a barrel from Fulton Armory.  This one closest fits what you're looking for (no flutes):

https://www.fulton-armory.com/barrelfatitan20nmm110ss1x12875gasblockthreaded.aspx

 

^^^  I have the 18.5" version of that barrel, and it's is just stupid-accurate.  It's on the same gun I was describing the recoil system on, above.

[98Z5V]

For how much it matters for a 1:9" twist on a .308 Win round - I've shot 185gr Berger Juggernauts through this gun, I've handloaded Hornady 195gr HPBTs for it, and I regularly shoot 178gr Hornady projectiles through it (just switched over to ELD-Xs from HPBTs) - and it is very, very accurate.  You shouldn't need a 1:9" for a .308 Win round, even using some pretty heavy projectiles.  I could see 1:9" if all you were gonna do is shoot 225s - but it's not necessary for typical "heavy" handloads or available loaded ammo.  1:10" twist will do fine for almost everything out there, unless you're going super-heavy. 

Edited February 19, 2020 by 98Z5V

[Cakey]

Thank you for the replies. Looks like I need to rethink my BCG and Buffer as well as gas block. And I'll take your barrel recommendation 98Z5V. I will probably end up hunting with bullets in the 180 grain line, I like the idea of being able to shoot heavy for caliber but I have a remington 700 for that and probably wouldnt much anyways. Thanks guys this is why I'm here. 

98Z5V have you tried Berger's 200.20x line? 

[98Z5V]

30 minutes ago, Cakey said:

98Z5V have you tried Berger's 200.20x line?

I haven't yet, but want to.  Those 185 Berger Jugs were loaded Federal Gold Medal Match ammo, and those things are stellar.  I couldn't believe the muzzle velocity from that load.

(Lemme grab my notes...  hold on a sec)

The day I verified my 178 ELD-X load, and re-zero'd my scope for it, resulted in this - this was final zero, called it here and reset the turrets:

This is the gun:

Even a Blind Monkey finds a banana once in awhile...    If I could'a kept my shiit together better, or didn't get nervous, or didn't jerk the trigger, those 3 could'a been touching. I was breathing heavy, hyperventilated, and just closed my eyes and started jerking the trigger again.  Trigger Tourette's, I guess, but I did something wrong.  Is what it is.  Story of my life. 

Back to numbers, that 178 ELD-X handload went through the chrono at 2530fps.  Not bad for a 178gr .308 Win projectile, and I'm keeping that load, for good. 

Those FGGM Berger 185gr Jugs went through the same chrono, same day, at 2557fps - those things are MOVING!  No pressure signs, so it's "not TOO hot," but that's a damn good load that they've got cooked up there. 

Many, many thanks to @Armed Eye Doc for those Jugs, too - I still have 4 1/2 boxes left, brother, for proper testing at distance.    I only went through a few, just to get those chrono numbers.  Now, I can make a chart for them, dial them right, and stretch them out a little.  

Since you're building, and looking for build info - here's the details on this gun:

 

Edited February 19, 2020 by 98Z5V