New Ultra Lite AR308 build - Page 1

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[ARCHIVED THREAD] - New Ultra Lite AR308 build

Posted: 3/9/2016 3:34:38 PM EDT

The goal is under 4.8 pounds using DPMS AR 308 pattern parts.

Just got my 2A Xanthos AR308 receiver set. I have a very low serial number!

The Xanthos receiver set weighs 16.25 ounces for both upper and lower. Consider the DPMS upper weighs 16 ounces! The Mega set weighs 29.6 ounces.

So far I have the lower done, complete @ 18.60 ounces. Waiting for the barrel. It would weigh 17.05 ounces if I used the 0.65 ounce New Frontier polymer Accu-trigger set.

Upper Parts:
2A Armament Xanthos Upper receiver 7075 T6 @ 9.00 ounces
X-Caliber 416R 16 inch fluted barrel @ 31.7 ounces
2A titanium gas block @ 0.60 ounces
Gas tube mid length @ 0.80 ounces
titanium muzzle brake @ 0.65 ounces
Clark Custom Aluminum barrel nut @ 1.18 ounces
AR 308 carbon fiber hand guard 1.60 ounces in mid length 10.5 inches
Toolcraft Titanium 308 BCG @ 11.80 ounces with ti firing pin
Vltor charging handle @ 1.25 ounces

Lower Parts: Total weight 18.60 ounces with SSA-E trigger

2A Armament Xanthos lower @ 7.30 ounces
Mag[Pul K grip @ 1.7 ounces[
V7 titanium grip screw 0.113 ounces
V7 Mag catch aluminum 0.173 ounces
V7 Aluminum/titanium selector 90 degree 0.293 ounces
V7 aluminum AR 308 takedown pins 0.26 ounces
V7 tool steel bolt catch 0.31 ounces
Smoke Composite stock 3.5 oz.
AR308 carbine buffer (no weights) 0.90 oz.
NF polymer trigger group 0.65 oz with titanium trigger pins
SSA-E trigger group 2.2 ounces with titanium trigger pins
DPMS carbine buffer spring @ 1.5 ounces
Titanium buffer retainer, mag catch plunger

Posted: 3/9/2016 4:02:34 PM EDT

[#1]

Every once in a while I score on eBay. Just got a titanium 308 muzzle brake 5/8-24 thread that weighs half an ounce less than any other if the seller is correct. Half an ounce is huge when at the front of the barrel. About 0.87 ounces less than my titanium Furion brake. Looks like the Weatherby Accubrake, there have been many others that look like this with the spiral hole patterns. The good thing is it doesn't need to be clocked.

Listed at 0.67 ounces. And only $55 with free shipping. Shipped the next morning

Here are all the lower small parts, minus pistol grip and buffer tube. Using aluminum V7 and titanium 2A parts almost 2 ounces are cut.

My Mag "K" grip is down to 1.7 ounces by a lot of dremmil work.

Posted: 3/9/2016 4:04:13 PM EDT

[#2]

Toolcraft titanium carrier with titanium firing pin 11.80 ounces

Posted: 3/9/2016 4:05:39 PM EDT

[#3]

Smoke Composites stock @ 3.3 ounces

Posted: 3/9/2016 4:05:41 PM EDT

[#4]

Looks awesome, So what's the total weight? 4.28 lbs?

Posted: 3/9/2016 9:43:02 PM EDT

[#5]

OP has money to blow, sweet. Looking forward to the total weight and a review describing recoil.

Posted: 3/9/2016 10:07:25 PM EDT

[#6]

Just to clarify so we're apples to apples.

The MATEN set weighs 27.4 according to MEGA - that's for the upper and lower. Don't go by the set as that includes the charge handle and actually an old weight listing.

Also, it includes the port door (.5oz), port door rod (approx. .2oz), take down pins (.7oz), springs/detents (approx. .1oz).

So completely stripped like the 2A set, it weighs in at a hefty 25.9oz. The 2A set is 9.6oz lighter than the MATEN, which is significant.

Posted: 3/9/2016 11:49:46 PM EDT

[#7]

Waiting for my barrel, it finished up at 31.3 ounces so I am expecting about 4.7 pounds for now. CF pistol grips might cut another ounce. I know barrels as light as 29 ounces have been made at 16 inch length. Just no one is selling them right now.

My other AR308 weighs 5 pounds even, recoil is greatly reduced with a good 2 chamber titanium V7 muzzle brake, reduced weight BCG titanium and a tune-able gas block.

Very low recoil, I have a BAD shooting shoulder. I can shoot 60-80 rounds of 175 SMKs with the 5 pound AR 308 no problem.

I will probably start shooting with the Mk 319 130 SOST ammo in the ultra lite 16 inch AR 308. I have 20 boxes and they are FUN to shoot.

Posted: 3/10/2016 2:20:20 PM EDT

[#8]

The finished re-profiled barrel ended up at 31.3 ounces

Posted: 3/10/2016 3:53:14 PM EDT

[#9]

Nice gun. Tagged for pics.

Posted: 3/12/2016 1:14:40 AM EDT

[#10]

This thread is so fucking tagged. Big fan of your work sir.

Can we get some pics of the R side of that upper?

Posted: 3/12/2016 2:03:10 PM EDT

[#11]

Right side, they put the serial number here instead of the normal left side.

Also they understand the 308, don't need a stinking forward assist.

Posted: 3/12/2016 2:09:23 PM EDT

[#12]

Thanks for the update on the MATEN set.

I have the lightest 10.5 inch AR 308 hand guard. CF tube is 1.60 ounces and latest barrel nut 1.18 ounces.

Posted: 3/12/2016 2:16:46 PM EDT

[#13]

Surprised the Vltor Charging handle (1.25 oz.) with larger catch weighs less than the smaller Strike Industries CH @ 1.40 ounces

Posted: 3/12/2016 7:05:37 PM EDT

[#14]

Tagged.

This is awesome!

Posted: 3/13/2016 12:38:14 AM EDT

[#15]

Quote History

Quoted:
Right side, they put the serial number here instead of the normal left side.

Also they understand the 308, don't need a stinking forward assist.

<a href="http://s1237.photobucket.com/user/brasse/media/2A_308XanthosBS3_zpse55xzdy7.jpg.html" target="_blank">http://i1237.photobucket.com/albums/ff464/brasse/2A_308XanthosBS3_zpse55xzdy7.jpg</a>

View Quote

godamn those receivers are sexy. Thx for the pic. Some inspration there for the hack job I am going to do to my Armalite set. I had planned on drilling holes above and below the grip screw hole, instead I ould do like 2A did and just grind away materal above and below it, it doesnt' need to go all the way across in a straight line. Some other cues I may follow. First thing i need it to get someone to do a side charger probably, if I have enough material there still.

was planning on drilling the deflector similarly too.

Posted: 3/19/2016 11:50:10 AM EDT

[#16]

AR 308 @ 4.8 pounds

Just finished the upper, came in at 58.4 ounces. With the lower at 18.6 ounces total weight is 77 ounces or 4.8 pounds.

I have to shoot it ASSAP, just so many projects at home.

In order to get down to 4.5 pounds I would have to have a 16 inch barrel weighing 29 ounces.

I know Salt Works has done a demonstration barrel at that weight. Maybe Faxon will produce a true pencil weight 308 barrel.

Also really want a lighter CF pistol grip. At 1.1 to 1.3 ounces it would cut 0.5 to 1.0 ounces over must grips.

They are now making titanium carrier pins for the AR15, logical to also make them for the 308.

Posted: 3/19/2016 8:07:55 PM EDT

[#17]

Guessing you've got the V7 aluminum end plate and castle nut.

Posted: 3/19/2016 10:11:11 PM EDT

[#18]

Quote History

Quoted:
Guessing you've got the V7 aluminum end plate and castle nut.

View Quote

Maybe no end plate? Ar10s* don't need them.

Smoke composites, who made the stock, make these parts much lighter than V7 even.

Posted: 3/19/2016 10:12:23 PM EDT

[#19]

Is that a custom length stock or a1 length?

I dunno about a Ti can pin OP, might gall w the carrier.

You could shed weight w a light profile on that carrier. But grinding Ti is like Satan's asshole.

Anyway, so far so great!

Post up some pron w the whole thing assembled

Posted: 3/20/2016 5:28:24 AM EDT

[#20]

This does not make the wait for my set to ship easier! All the machining in spec and looking good?!?

Posted: 3/24/2016 3:48:31 PM EDT

[#21]

Any follow up? How does she shoot?

Posted: 3/24/2016 5:12:47 PM EDT

[#22]

Quote History

Quoted:
AR 308 @ 4.8 pounds

Just finished the upper, came in at 58.4 ounces. With the lower at 18.6 ounces total weight is 77 ounces or 4.8 pounds.

I have to shoot it ASSAP, just so many projects at home.

In order to get down to 4.5 pounds I would have to have a 16 inch barrel weighing 29 ounces.

I know Salt Works has done a demonstration barrel at that weight. Maybe Faxon will produce a true pencil weight 308 barrel.

Also really want a lighter CF pistol grip. At 1.1 to 1.3 ounces it would cut 0.5 to 1.0 ounces over must grips.

They are now making titanium carrier pins for the AR15, logical to also make them for the 308.

<a href="http://s1237.photobucket.com/user/brasse/media/2A_308XanthosUpper%2058.4oz_zpsz9wtmeor.jpg.html" target="_blank">http://i1237.photobucket.com/albums/ff464/brasse/2A_308XanthosUpper%2058.4oz_zpsz9wtmeor.jpg</a>

<a href="http://s1237.photobucket.com/user/brasse/media/2A_308XanthosLower18.60ozLarge_zpsiefyn4n7.jpg.html" target="_blank">http://i1237.photobucket.com/albums/ff464/brasse/2A_308XanthosLower18.60ozLarge_zpsiefyn4n7.jpg</a>

View Quote

Check with 2A. They have us making some fun stuff for them to match with the upper!

Posted: 3/24/2016 6:14:45 PM EDT

[#23]

great job!

how much did this build cost?

Posted: 3/29/2016 10:48:19 AM EDT

[#24]

Waiting on the money shot...

Posted: 3/29/2016 3:07:58 PM EDT

[#25]

Nice!

Posted: 5/13/2016 11:47:41 PM EDT

[#26]

so is this thread over now?

Posted: 5/14/2016 12:30:36 AM EDT

[#27]

Quote History

Quoted:

so is this thread over now?

View Quote

I hope not...this is fascinating!!!!

Posted: 5/15/2016 10:33:54 AM EDT

[#28]

That is amazing!

I have been pondering on some weight reduction for my 16" 308, but not anywhere like this haha.

Posted: 5/18/2016 9:45:23 PM EDT

[#29]

We managed to get the XANTHOS-lite production gun down to 6.75 lbs before I left 2A. I spec'd the rifle as such.

2A Xanthos upper/lower
2A Titanium pins
2A X4 titanium brake
2A .308 Rail "Style 2"
2A Lightweight barrel 1/10 5R 18" .308 Match chamber Rifle length gas system .093 gas port
Full mass internals

A5 Extension
Springco Orange
H3 Buffer
P-MAG
MIAD Grip
Mission First stock
CMC 2/2 trigger

So in the end you have a full rifle gas 18" gun with full mass internals, A5 extension, that shoots nice and soft, and is only 6.75 lbs. Not sure how far along they are with it now though, but I know they are all excited.

thanks OP for starting this thread!

Ryan

Posted: 5/20/2016 6:13:39 AM EDT

[#30]

Quote History

Quoted:
We managed to get the XANTHOS-lite production gun down to 6.75 lbs before I left 2A. I spec'd the rifle as such.

2A Xanthos upper/lower
2A Titanium pins
2A X4 titanium brake
2A .308 Rail "Style 2"
2A Lightweight barrel 1/10 5R 18" .308 Match chamber Rifle length gas system .093 gas port
Full mass internals

A5 Extension
Springco Orange
H3 Buffer
P-MAG
MIAD Grip
Mission First stock
CMC 2/2 trigger

So in the end you have a full rifle gas 18" gun with full mass internals, A5 extension, that shoots nice and soft, and is only 6.75 lbs. Not sure how far along they are with it now though, but I know they are all excited.

thanks OP for starting this thread!

Ryan

View Quote

You left? :(
Good terms? Bad Term? Where did you move to?

Posted: 5/20/2016 6:20:39 AM EDT

[#31]

Guess that's why it's been quiet over on the industry page.
Other endeavors I assume?
Standard or adjustable block?

Quote History

Quoted:
We managed to get the XANTHOS-lite production gun down to 6.75 lbs before I left 2A. I spec'd the rifle as such.

2A Xanthos upper/lower
2A Titanium pins
2A X4 titanium brake
2A .308 Rail "Style 2"
2A Lightweight barrel 1/10 5R 18" .308 Match chamber Rifle length gas system .093 gas port
Full mass internals

A5 Extension
Springco Orange
H3 Buffer
P-MAG
MIAD Grip
Mission First stock
CMC 2/2 trigger

So in the end you have a full rifle gas 18" gun with full mass internals, A5 extension, that shoots nice and soft, and is only 6.75 lbs. Not sure how far along they are with it now though, but I know they are all excited.

thanks OP for starting this thread!

Ryan

View Quote

Posted: 5/26/2016 9:41:57 PM EDT

[#32]

I am interested in this build for sure. I owned three AR10s and they shot great, but the weight turned me off.

Posted: 5/26/2016 10:30:50 PM EDT

[#33]

I IM'd OP. test and Tren back in and let us know power suits and maybe post up some pictures of The Thing complete. He has been around last week apparently

Posted: 5/27/2016 10:02:57 AM EDT

[#34]

Quote History

Quoted:
Guess that's why it's been quiet over on the industry page.
Other endeavors I assume?
Standard or adjustable block?

View Quote View All Quotes

View All Quotes

Quote History

Quoted:
Guess that's why it's been quiet over on the industry page.
Other endeavors I assume?
Standard or adjustable block?

Quoted:
We managed to get the XANTHOS-lite production gun down to 6.75 lbs before I left 2A. I spec'd the rifle as such.

2A Xanthos upper/lower
2A Titanium pins
2A X4 titanium brake
2A .308 Rail "Style 2"
2A Lightweight barrel 1/10 5R 18" .308 Match chamber Rifle length gas system .093 gas port
Full mass internals

A5 Extension
Springco Orange
H3 Buffer
P-MAG
MIAD Grip
Mission First stock
CMC 2/2 trigger

So in the end you have a full rifle gas 18" gun with full mass internals, A5 extension, that shoots nice and soft, and is only 6.75 lbs. Not sure how far along they are with it now though, but I know they are all excited.

thanks OP for starting this thread!

Ryan

It did not have an adjustable block, however knowing the crew, a .308 RBC SHOULD be in the works.

I won't say good or bad on leaving.... I can say I will remain in the industry, but will wait to say where I am going for now. I am very excited however!

Ryan