First 308 build [Archive] - Weapon Evolution

mustangfreek

20 March 2019, 22:58

Allright fellas... never had one, always wanted one...well a deal I couldn’t pass up popped up , so after a drive to Rainier Arms , here’s the start to the first large frame AR I’ve had or built. Wanting something to punch paper, shoot steel and use to hunt as the itch to is there.

So the base of the build will be on this Aero Precision M5 lower and upper. Lower is complete from Aero with their LPK, AR-15 carbine length tube and shorty buffer and their spring.. I have been eyeballing the Armaspec SRS setup for my battkekitty , but I might test it out in this..TBD..

Back to the 308 here..starting out as

Aero M5 lower -complete as built from aero.
Aero M5 upper
Fortis CH
Toolcraft/brownells nitride BCG

I’ve got a Magpul grip for it laying around, and I think a barrel has been sourced.Think I’m just gonna run a A2 for now. As a suppressor setup is hard on the mind and would need their mount..so...TBD..

Then just gas tube and block, which still unsure to go adj. from the get go or just a std for now then swap later..etc..

Oh and handguard, looking for a 15” ‘ish mlok something.. I want a cmt , but funds might have to settle on a aero something for now.. about a bill cheaper too..which is Ammo money in my mind..

Quick old iPhone pic to get this started..

UWone77

21 March 2019, 04:03

You’re welcome [:D]

mustangfreek

21 March 2019, 04:25

You’re welcome [:D]

Haha...I can’t say thank you enough for all the help..and being a friend...it’s hard to come by now a days...#nohomo...[BD]

I’m excited to getting this done.

UWone77

21 March 2019, 05:30

Haha...I can’t say thank you enough for all the help..and being a friend...it’s hard to come by now a days...#nohomo...[BD]

I’m excited to getting this done.

What parts are you short again?

Handguard? That pretty much it?

Sights?

mustangfreek

21 March 2019, 15:22

After I play swap around with the now , parts gun. I should only need gas block,tube, handguard to get it up and running..

Well that and I’m gonna need to borrow or buy a reaction rod tool or such along with the go/no go guages.. not really setup for putting together big boy ARs yet.

Sights...not sure... might have to rob the 1-4 off the battlekitty for now.

Jerry R

21 March 2019, 15:46

Can't help with the gauges, but I have a 308 reaction rod you can borrow. When you are ready for it, if you still need it, PM me with a shipping address.

Joelski

21 March 2019, 18:38

Get the Seekins (fixed it) adj gas block. It's cheap, relative to others and it works. Save the money you'd spend on that gamble because 9 out of ten, you'll need it.

BoilerUp

23 March 2019, 07:36

Unless you are really planning out a lightweight build, I can't recommend the 2A Xanthos primarily becuase I absolutely hate their mounting system. You put 2 screws on each side that are angled back and 45 degrees to lock into the barrel nut. As you torque the screws the rail itself "yaws" about the horizontal barrel axes. It looks cool and is very light, but is a niche product IMO.

https://photos.smugmug.com/photos/i-Gmw5rcK/0/e55a18e9/X3/i-Gmw5rcK-X3.jpg

Joelski

23 March 2019, 19:33

I'd watch the rail board on m4c for as long as it takes until a Geissele rail pops up, but that's just me.

My next build will be the Radian AR 762.

fledge

23 March 2019, 19:50

Can’t wait to see a radian 308!

I have the Xanthos rail too. The mount is weird but I must admit it’s solid. I’ve carried it all over the woods in hunting seasons without issue. Every once in a while they offer blems for $99.

If you want a new Xanthos 2a upper with blem rail, I’ll sell it to you at my cost. I have an extra set.

Joelski

24 March 2019, 07:35

Didnt think there was a size difference as it fits over the barrel nut. Rail height is another matter, so there ya go. Good luck.

SINNER

24 March 2019, 08:45

The barrel nut is proprietary to the rails on .308’s and vary based on the platform. AR-10 (Armalite & Noveske) barrel nuts are 1 7/16-18 thread and DPMS (SR-25) are 1 7/16-16 thread. Definitely not interchangeable with AR-15’s that are 1 1/4-18.

mustangfreek

24 March 2019, 19:29

Quick pic from last nite, crappy quality..but I just got a new phone finally..been rocking a cracked I5 for ...um..years

Anyways...brownells/toolcraft/ looks identical to the Aero bcg’s....will see I guess thru them being on sale and codes along with AJ this was right at a $100 shipped, staked well and everything looks good..

Pyzik

25 March 2019, 06:00

Get the Seekins (fixed it) adj gas block. It's cheap, relative to others and it works. Save the money you'd spend on that gamble because 9 out of ten, you'll need it.

This. I messed around and messed around before I just bit the bullet and got an adjustable gas block.

SINNER

26 March 2019, 01:46

Gas blocks = failure prone band aids for improperly set up buffer systems. Even worse on large pattern AR’s for slowly clogging and causing malfunctions.

BoilerUp

26 March 2019, 07:19

Gas blocks = failure prone band aids for improperly set up buffer systems. Even worse on large pattern AR’s for slowly clogging and causing malfunctions.

I'm sure you have more experience than I do, and maybe I'll come around to your point of view eventually, but for large frame AR's I think it's best to just go ahead and start off with an AGB. There is more variability across manufacturers, more reciprocating mass, and more variability in ammo (across milsurp 7.62x51 to commercial .308 Win). Suppressor use also really affects things. Not always required, but dropping $100 on an SLR Sentry is a good way to let you tune your system.

gatordev

26 March 2019, 12:58

mustangfreek

26 March 2019, 14:21

As far as what works or?

Std ar15 tube = shorty 308 buffet and 308 spring

Ar10/A5 length = std ar15 buffer and 308 spring such as the ArmaLite one.

There’s more to it then that, I’m lookimg hard at that Arnaspec SRS setup- it’s a 2 stage sorta captured unit with 5.6 oz. buffer weight vs the std shorty at 3.8 ‘ish oz.

Former11B

26 March 2019, 18:23

Tuning the proper gas flow itself is the way to go rather than throwing heavier and heavier buffers at the problem. Ideal would be a properly sized gas port but in the age of multiple setups/configurations between ammo, suppressors etc. Its not as easy as changing a buffer but it’s addressing the problem at the source. And they will no more clog up than a regular gas port/block if they’re designed properly

Tossing a heavy buffer into an overgassed rifle is a mask for the symptom and does nothing to take care of the real problem at hand

I would say there are some occasions where I wouldn’t change the block out, like a Factory built rifle I want to leave as-is. In that case, a Gemtech carrier or something might be appropriate, but I would swap the buffer in this case

Joelski

26 March 2019, 19:20

^^ This OR...

How about premium barrel makers stop making barrels that cater to people who want to run the cheapest, shittiest, garbage ammo they can get on armslist? I know I'm going out on a limb, but I'm willing to say that if people spend money for a decent barrel, they'll be willing to spend to feed it well.

How about if you make a barrel, supply a gas block that you guarantee will work with your dimensions.

Why does it have to be the way it currently is? If somebody wants to fiddlefuck with their gun, fine, but if you want $500 or more for a barrel, make it work out of the box without having to fuck with it.

Make a gas block that works like a piston set-up with settings for U-S-O.... Why hasn't the switchblock caught on, other than it costs too damn much?

BoilerUp

26 March 2019, 19:32

Piggy-backing on this thread...

I'm trying to "reset" a configuration and I'm not 100% sure what I have vs. need. Is there an Vltor A5 Guide for Dummies somewhere? I think either BoilerUp or Former11B broke it down recently, but I can't seem to find it again.

http://www.weaponevolution.com/forum/showthread.php?10994-308-Aero-M5-build-questions&p=165543&highlight=#post165543

gatordev

27 March 2019, 06:58

http://www.weaponevolution.com/forum/showthread.php?10994-308-Aero-M5-build-questions&p=165543&highlight=#post165543

That was it. Thank you. I'm actually trying to reduce buffer weight, not add to it. For clarification...

The VLTOR A5 buffer tube is simply an Armalite AR-10 carbine sized receiver extension with a specially designed buffer for the AR-15. If you use an Armalite carbine receiver extension (i.e., an A5), on a large frame build, you need to use a standard AR-15 carbine buffer and the Armalite buffer spring (https://www.rainierarms.com/armalite...buffer-spring/). If you use the A5 buffer, you likely won't cycle properly, and if you use the DPMS 308 carbine buffer (the short one), the bolt will slam into the lower receiver and cause damage. If you ever seen damage to the threads on the lower where the buffer tube threads in, you've got a mismatched buffer setup. Guess how I know that.

I didn't realize you could run a carbine buffer in an A5/AR-10 spring. That greatly simplifies my problems and means I may not have to buy anything. But I thought the point of the Vltor system was that it worked in harmony with the A5 buffer system? It mentions it's compatible on their site, even for .308.

Like I said, I'm happy to not have to buy anything else, just confused.

SINNER

27 March 2019, 07:19

If you want a large frame AR to run correctly, a rifle length buffer system and rifle length gas system. End of discussion. A5’s are not much better than a carbine system and carbine systems flat out suck on a .308.

And ALL gas blocks can and will clog and cause the system to slowly lose the correct gas charge. Much more quickly on a .308 rifle. Less than 300 rounds on my one 6.5 and it was failing to eject. The heat had also seized the adjustment screw on the gas block rendering the entire rifle inoperable. $100 poorly designed band aids.

mustangfreek

27 March 2019, 13:58

gatordev

27 March 2019, 15:12

What buffer are you running now with the A5 setup?

I hear most people using a A5 tube , are using a H3 buffer along with the 308 ArmaLite spring ..

I’m hearing what sinner is saying also..

What's installed wasn't a bandaid, it was a triage compression bandage for a previous barrel. But what I will be switching out is a Slash .308 XH Carbine buffer (8.5 oz). It's way too heavy for...well...anything with the new barrel. I'll throw some AR-15 buffers at it after my next work hitch to see what works.

BoilerUp

27 March 2019, 19:51

I didn't realize you could run a carbine buffer in an A5/AR-10 spring. That greatly simplifies my problems and means I may not have to buy anything. But I thought the point of the Vltor system was that it worked in harmony with the A5 buffer system? It mentions it's compatible on their site, even for .308.

Like I said, I'm happy to not have to buy anything else, just confused.

The A5 buffer tube is simply the Armalite AR10 carbine buffer tube. Then they lengthened the buffer (for the AR-15). I think what VLTOR is trying to tell you is that you can use the A5 tube on an AR-15 with the A5 buffer, or you can use it as an AR-10 carbine buffer tube - because they're the same thing (but NOT with the A5 buffer).

So, to be clear, if you use the A5 tube on an AR-15, you need the AR5 buffer. If you use it on a 308, you use the AR-15 buffer. Which is why everyone gets confused when you start talking about buffer systems on the 308.

In summary, you have 3 choices for the buffer system on the large frame:

Rifle - tube/buffer/spring are same on AR10 and SR25
Armalite Carbine - longer buffer tube (= Vltor A5) with AR15 carbine buffer, Armalite Carbine Spring
SR25 Carbine - AR-15 tube with DPMS 308 buffer (shorter than AR15 carbine buffer), AR15 carbine spring

Personally, I have two Large frames builds:
M5 with DPMS/AR-15 carbine buffer tube, JP 308 SCS, JP LMOS BCG, Sentry 7 AGB
Xanthos with 2A buffer tube which is AR-10 carbine length, JP AR-15 SCS with small plug, Sntry 7 AGB, JP LMOS BCG

Both run fine after tuning the gas with the Sentry AGBs so I didn't have to futz with the buffer weight. I'm loathe to add weight to a buffer because less reciprocating mass = less felt recoil = easier to keep eyes on target and trace. I'm also loath to add strong springs because of the noticeable impact on charging and cyclic rate. Fix the gas first. Neither of the above rifles are built as duty guns, but I'd probably just get a MARS-H/MWS and call it done if that's what I needed.

gatordev

28 March 2019, 02:38

Got it! Thank you. It's much clearer now.

Joelski

28 March 2019, 07:31

Just buy a Colt! (R)

BoilerUp

11 April 2019, 15:02

Well cause I can’t leave shit alone....[BD]...Ditching the carbine DPMS/short buffer setup.

Thinking hard about putting a A2 stock on this thing.

Personally, I don't think the extra length of spring and associated effect on felt recoil is worth the trade-off for losing the adjustable stock. I prefer the Armalite AR-10 carbine (A5) system as a good compromise.

SINNER

12 April 2019, 03:13

Only buffer that works correctly on large frame AR’s IMO. Unless you find the rare barrel with a properly sized gas port.

Go with a PRS. Worth every penny on a .308 rifle.

BoilerUp

13 April 2019, 01:31

My favorite carbine stock for shooting from the bench without adding a lot of weight is the Magpul STR. Great check weld like a SOPMOD, but works very well with a rear sandbag. Primary has them on sale for $58, too.

mustangfreek

24 April 2019, 01:47

Package from Armalite, their 308 buffer kit
-A5 length Mil-Spec tube, H3 buffer and their 308 sprin, nut and Ambi plate (which I’m not using)

Threads in nice and tight into lower, stock fits tight , for $60 shipped , it’s a good value I feel, time will tell though.

Note to self, these frickin hexmags were so tight, like not going in. So took some sandpaper to them to make them useable. Good thing I only got 2, need some more pmags.

mustangfreek

25 April 2019, 16:48

Update #2

Swapped in the H2 from my other lower into this.

-put 2 rounds of federal 308 165gr. Nosler, fired both and locked back the bolt.
But wow, definitely way more recoil everywhere, brass to about the 1 o’clock position.

- loaded up 2 LC 147gr xm80 Ambi, fired both no problems and locked the bolt back. Felt a little less brutal then the 308. Brass about the 4 o’clock.

- then thru in 2 Wolf 150gr FMJ-BT, fired one, no lock back..then chambered another, no fire. Primer was dented pretty good from firing pin, tried it again. Click. Thru that one away.

-Loaded 2 more wolf 308rds. Fired them both and locked the bolt. Brass about 4-5 o’clock , did it one more time, again locked back , same spot for brass.

So, I don’t like the recoil impulse with the H2, but right now it won’t work with the wolf , with the H3.

Sorta sounds on the low end for gas. No adjustable block, but really don’t want one. I like my guns to run on anything I feed them.

One thing I’ve noticed is, when pulling on the CH to pull big back, it seems to be really tight coming out of the lugs. Seems like more force is needed then what should be...or this first ar10, is really a learning curve when piercing one together per say.

I thought about trying a tubbs flat wire , from the get go, but just went with the Armalite kit.

Any info , or ideas would be great.

BoilerUp

25 April 2019, 20:25

run it for a few hundred rounds and let it break in. Sounds like it's fine. Doesn't this have a Rainier Match barrel? If so, please stop feeding it Wolf. It deserves better.

I've generally formed the opinion that you need to decide if you want a .308 or a 7.62x51. You've got a .308 build, so tune it for commercial .308 (which sounds like you should put the H3 back in) and stop trying to feed it cheap milsurp ammo. As your post attests to, the difference is very noticeable in a gas gun.

Joelski

26 April 2019, 10:49

I've not really noticed recoil from mine, using standard Aero carbine kit. It's far closer to a 5.56 than a .243 in terms of kick.

UWone77

26 April 2019, 10:59

I agree with Boiler. This is an UltraMatch barrel, don't feed it wolf. Put the H3 back in and shoot the 308, not the crappy 7.62x51. This barrel has a break in period.

Also if the wolf seems to be undergassed, an adjustable won't help that, but I'm sure you knew that.

I'll have to look at my stash, but if I'm just plinking with my UM barrels, I'll shoot the bulk Federal or Winchester 308 ammo, no wolf.

BUT... I'm glad you got this together.

SINNER

26 April 2019, 14:00

Now you know why I said carbine buffer systems suck on .308’s. No happy medium possible. Any ammo I’ve shot either suppressed or a just brake functions in ALL my large pattern AR’s with a rifle length buffer system. The one I have with a carbine system is a pain in the ass. Either feels like it’s beating itself apart or it fails to feed correctly. Adjustable gas blocks do nothing to help unless you readjust for every ammo change.

Joelski

26 April 2019, 16:02

Man, I sure am glad I have fun shooting guns.

BoilerUp

29 April 2019, 20:31

I’ll update the list, but scavenged off my other AR and swapped stuff around.. pretty happy with it.

Ended up with an A2 for now.. Hoping later this year I can put down $$ for a can. So will wait for whatever mount accompanies whatever’s can

Question though...I know brakes are loud AF, how good are they for the 308’s??

I put an older PWS FSC on a PTR91 and it made a huge difference in felt recoil. But you don't want to stand next to it. Behind it isn't so bad. I've got a Griffin Brake my .308 and accidently shot it w/o ear pro. That hurt. Can't speak to its recoil reduction because I never shot that rifle w/o the brake or a can. I like the brake as a sacrificial baffle, too. And I was never good at making friends at the range, anyway.

UWone77

29 April 2019, 21:35

You inspired me to finish my Aero 6.5... taking it to the range next week. 18" Ballistic Advantage barrel.

6494

Jerry R

18 May 2019, 05:33

Nicely done! Great looking rifle. Glad I'm not the only one that puts "ladders" on the top rail [BD]

Former11B

29 July 2019, 16:18

Ever plan on getting a can? If so, get one that doubles as a suppressor mount from the company you like the cans from.

Otherwise try this:

https://www.midwayusa.com/product/2367125087/pri-muzzle-brake-quiet-control-5-8-24-thread-ar-10-lr-308

chris1976

29 July 2019, 17:47

VG6 on mine, was put on from day one so dont know how much louder it got but its loud lol but it also has very little recoil...

Sent from my SM-G950U using Tapatalk

UWone77

30 July 2019, 14:02

Yes on the can, was recently saving all my AJ/Ebates for a can..well life and kid graduating kinda ate all extra funds. So..

I do want at least one 762 can along with a 556 and 22 suppressor..

No $50 minis around here....lol

Put the kid to work since he graduated and take his paychecks. LOL

UWone77

30 July 2019, 14:22

VG6 on mine, was put on from day one so dont know how much louder it got but its loud lol but it also has very little recoil...

Sent from my SM-G950U using Tapatalk

I like the VG6, in face if you don't do the Epsilon/Gamma, you could do the Lambda.

Lantac Dragon also an option.

Former11B

30 July 2019, 16:05

I like the VG6, in face if you don't do the Epsilon/Gamma, you could do the Lambda.

Lantac Dragon also an option.

The people around you (or you indoors) will hate you

BoilerUp

30 July 2019, 18:33

The people around you (or you indoors) will hate you

The PWS FSC takes a lot of recoil out of my PTR91 but man you don't want to be next to it.

If looking to suppress, the Griffin Armament brakes are quite effective and provide the taper mount capability.

mustangfreek

30 July 2019, 23:42

Ya I had a dragon with a 16”-556... damn...traded that away..[BD]

I don’t want the loudest mofo..just something to take some of the hit out of it.

I like griffins stuff. I get ya on the get a muzzle device for a can down the road.. truth is I haven’t kept up on the suppressor game so unsure what I want to do..

Put the kid to work since he graduated and take his paychecks. LOL

Lol..