Building lightweight AR10 - VSeven Harbinger vs 2A Xanthos Lite vs other?

[LilGucci]

HI. I'm going to be buying a receiver set for a lightweight AR10 build I'm doing next Spring. The only two I'm aware of is the Vseven Harbinger, and the 2A Xanthos Lite. Do any of you have any experience with either of these receiver sets? Would you recommend them? I'm going to be using a Proof Research barrel with this build. I don't care much for the aesthetics as both look very good. Do you know of any other lightweight alternatives to these two?

2A Armament is no longer in business, NEMO bought their tooling out and put them out of business. Would that be a no-go for you? There are plenty of 2A parts still around, but I don't know if I should be worried about that being an issue.

I want the rifle to be lightweight, so I might go with 6.5 Creedmoor to make it even lighter to trek the countryside with. If you were building a lightweight AR10, which caliber/cartridge would you go for?

Any recommendations would be helpful.

 

[Coffee_and_Pipes]

I don’t have experience with either of those companies, but I remember reading a thread about a lightweight 2A build. It’s been a while since I’ve read through it, but I hope it has some useful information for you.

https://www.snipershide.com/shooting/threads/lightweight-2a-arms-xanthos-6-5-cm-build.6877340/

 

[Hecouldgoalltheway]

Can I ask why you want a lightweight ar10 so bad? A lightweight ar10 is a paradoxical statement, an oxymoron if you will. If you want a 6lb 6.5cm, easy..

You want a 6lb ar-15 capable of hunting use up and beyond 400lb animals.... 6arc.

Everything about a properly functioning ar10 is heavy.

 

[KYAggie]

Can I ask why you want a lightweight ar10 so bad? A lightweight ar10 is a paradoxical statement, an oxymoron if you will. If you want a 6lb 6.5cm, easy..

You want a 6lb ar-15 capable of hunting use up and beyond 400lb animals.... 6arc.

Everything about a properly functioning ar10 is heavy.

I used to think that too, and perhaps if you were going to war, you might be correct, I don’t know, I haven’t and mine will likely never see that kind of use, but baring that heavy use, I was wrong. That is my 6.5 in that post above and I have a 308 built in a similar fashion weighing right at 6# and both have given me no issues and they are properly functioning. It’s amazing the weight you can carve from an AR10 platform if you have the money to fill it with titanium parts and a carbon hand guard. I don’t have carbon hand guards on either of mine, but could make them lighter if I did. Interestingly, they are both very soft shooting; not slinging a heavy bolt carrier around makes a huge difference. You absolutely must have a good AGB and tune it properly, but after that it will run.

Oh, and the light weight makes them nice in the field for hunting.

 

[Hecouldgoalltheway]

I used to think that too, and perhaps if you were going to war, you might be correct, I don’t know, I haven’t and mine will likely never see that kind of use, but baring that heavy use, I was wrong. That is my 6.5 in that post above and I have a 308 built in a similar fashion weighing right at 6# and both have given me no issues and they are properly functioning. It’s amazing the weight you can carve from an AR10 platform if you have the money to fill it with titanium parts and a carbon hand guard. I don’t have carbon hand guards on either of mine, but could make them lighter if I did. Interestingly, they are both very soft shooting; not slinging a heavy bolt carrier around makes a huge difference. You absolutely must have a good AGB and tune it properly, but after that it will run.

Oh, and the light weight makes them nice in the field for hunting.

Nice rifle. What would you estimate that rifle cost you to get so light? I'm adding it up in my head and it looks like you're probably pushing $4k in parts, am I in the ballpark?

 

[KYAggie]

Here’s a few pictures of my Faxon Gunner weight 16”barreled 6# empty AR10 on my clubs 600 yard range. Take a look at the 10 ring and x ring as I walked my shots into it on the electronic target with a bastard old Leopold illuminated 4.5-14 Mark 4 with TMR reticle and MOA turrets . I got really lucky with that Faxon barrel. Light AR10’s can perform; who knew.

 

[KYAggie]

Nice rifle. What would you estimate that rifle cost you to get so light? I'm adding it up in my head and it looks like you're probably pushing $4k in parts, am I in the ballpark?

I bought parts on sale over two years before I put those together, so I have about $2400 in each one, but that was 2015-2017 time frame. So yeah, full retail in today’s money would very likely put them in the 3k to 4k range I would guess. I paid $120 for that Faxon 308 barrel on sale a Brownells for example and my most expensive titanium bolt carrier was that Cryptic Coatings one in the 6.5 and it was a blem on sale for $350. It’s not cheap to go light. I bought blem received sets from 2A for $450 instead of the $700+ range and I don’t know why they were blems.

 

[msgriff]

Another lightweight manufacturer is Roam Rifles. They re magnesium alloy, so look into the downside of that. The lowers have also been OOS for quite a few months. Receiver sets are around 15.4oz . Complete rifles with 16" 308 steel barrels are around 6.1 lbs, that's with a FMOS and not a lot of exotic parts.
Also, a 6.5 Creedmoor barrel is not lighter in weight than an identical length/profile barrel in .308, but the difference in weight would be insignificant, IMO.

 

[knuckleballz]

https://www.snipershide.com/shooting/threads/super-light-premium-ar10.7213724/ Not sure if this is still for sale

 

[LilGucci]

I don’t have experience with either of those companies, but I remember reading a thread about a lightweight 2A build. It’s been a while since I’ve read through it, but I hope it has some useful information for you.

https://www.snipershide.com/shooting/threads/lightweight-2a-arms-xanthos-6-5-cm-build.6877340/

Hey thanks, that thread is a goldmine. Appreciate it

 

[LilGucci]

Can I ask why you want a lightweight ar10 so bad? A lightweight ar10 is a paradoxical statement, an oxymoron if you will. If you want a 6lb 6.5cm, easy..

You want a 6lb ar-15 capable of hunting use up and beyond 400lb animals.... 6arc.

Everything about a properly functioning ar10 is heavy.

I have two AR10's and I'd like to try something different. I thought about straight up buying a Harbinger but I'd rather build something with the parts that I want, namely a BCG from JP and a Proof barrel.

 

[LilGucci]

Another lightweight manufacturer is Roam Rifles. They re magnesium alloy, so look into the downside of that. The lowers have also been OOS for quite a few months. Receiver sets are around 15.4oz . Complete rifles with 16" 308 steel barrels are around 6.1 lbs, that's with a FMOS and not a lot of exotic parts.
Also, a 6.5 Creedmoor barrel is not lighter in weight than an identical length/profile barrel in .308, but the difference in weight would be insignificant, IMO.

I think I saw Honest Outlaw do a review on it. I'll check it out, that is incredible weight. I'm targeting sub-7lbs.

 

[MSTN]

I'm a big fan of cutting weight where possible, but not performance. I don't care for compromises resulting from things like ultra-light buttplates, skeletonized pistol grips, and lightweight buffer systems.

2A Armament and V Seven build absolutely beautiful lightweight yet fully functional receiver sets and forends. Battle Arms Development used to make a solid lightweight big block receiver set and rail, as well. I'm sorry to see 2A and BAD designs go. Between the three, from my perspective, V Seven gets the nod due to a more robust barrel nut design.

The heaviest component in most rifles, not just gas guns, is the barrel. In big block gas guns, going with a Proof carbon fiber barrel is a proven way to reduce weight, but not performance - with added cost, of course. You can get excellent performance out of a 16" .308 barrel, but I think 20" is a more appropriate minimum length for the 6.5 CM. In Proof CF barrels, this is an immediate 11 ounce advantage going with caliber .308.

A second gas gun component with considerable mass is the bolt carrier group. While you can go lightweight or reduced mass here with .308, it's not a good idea to do other than full mass with the 6.5 CM. In JP bolt carrier groups, this is another 4.5 ounce advantage going with caliber .308.

In recoil buffers, I've found that with an adjustable gas block, an H2 is ideal with the above combo. In .6.5 CM, the H3 works better. There's another 1.5 ounce advantage going with .308.

The net result is a 16" .308 with Proof CF barrel and low mass bolt carrier group will weigh about a pound less than an otherwise identical 20" 6.5 CM with Proof CF barrel and full mass bolt carrier group. This works out to 7 pounds for a 16" .308, and 8 pounds for a 6.5 CM.

That's just the rifle. A 16" .308 is well served by a low power variable optic, while most of us would opt for a high power variable optic for 6.5 CM. More weight.

To sum up, a 16" .308 with top shelf high dollar components and optic is going to end up 1.5 pounds lighter than its 6.5 CM cousin.

Some photos of past projects:

 

[MSTN]

If you're looking for the best performance related return on investment (i.e., "weight"), just skip the big block game and build a 6 ARC with a Proof CF barrel.

 

[ut755ln]

That's just the rifle. A 16" .308 is well served by a low power variable optic, while most of us would opt for a high power variable optic for 6.5 CM. More weight.

To sum up, a 16" .308 with top shelf high dollar components and optic is going to end up 1.5 pounds lighter than its 6.5 CM cousin.

First, I love looking at your builds. Second, you actually replied to the post with a well thought our argument for .308. Last, my 16" LMT in 6 ARC weighs less. cost less and shoots flatter and longer (probably).

 

[Cascade Hemi]

Roam and V7 are about the only lightweight specific receiver sets around anymore. The SLR B36 receiver set isn't exactly lightweight but only weighs 20oz combined compared to the B30 set's 26oz.

 

[LilGucci]

I'm a big fan of cutting weight where possible, but not performance. I don't care for compromises resulting from things like ultra-light buttplates, skeletonized pistol grips, and lightweight buffer systems.

2A Armament and V Seven build absolutely beautiful lightweight yet fully functional receiver sets and forends. Battle Arms Development used to make a solid lightweight big block receiver set and rail, as well. I'm sorry to see 2A and BAD designs go. Between the three, from my perspective, V Seven gets the nod due to a more robust barrel nut design.

The heaviest component in most rifles, not just gas guns, is the barrel. In big block gas guns, going with a Proof carbon fiber barrel is a proven way to reduce weight, but not performance - with added cost, of course. You can get excellent performance out of a 16" .308 barrel, but I think 20" is a more appropriate minimum length for the 6.5 CM. In Proof CF barrels, this is an immediate 11 ounce advantage going with caliber .308.

A second gas gun component with considerable mass is the bolt carrier group. While you can go lightweight or reduced mass here with .308, it's not a good idea to do other than full mass with the 6.5 CM. In JP bolt carrier groups, this is another 4.5 ounce advantage going with caliber .308.

In recoil buffers, I've found that with an adjustable gas block, an H2 is ideal with the above combo. In .6.5 CM, the H3 works better. There's another 1.5 ounce advantage going with .308.

The net result is a 16" .308 with Proof CF barrel and low mass bolt carrier group will weigh about a pound less than an otherwise identical 20" 6.5 CM with Proof CF barrel and full mass bolt carrier group. This works out to 7 pounds for a 16" .308, and 8 pounds for a 6.5 CM.

That's just the rifle. A 16" .308 is well served by a low power variable optic, while most of us would opt for a high power variable optic for 6.5 CM. More weight.

To sum up, a 16" .308 with top shelf high dollar components and optic is going to end up 1.5 pounds lighter than its 6.5 CM cousin.

Some photos of past projects:

Thank you so much for this review. I think I'll go with 308 then in the 16-inch Proof CF barrel. I also think I'll go with the VSeven, the reviews I've watched and read also mentioned the handguard/barrel nut design. I can't thank you enough. Beautiful rifles too!

 

[LilGucci]

If you're looking for the best performance related return on investment (i.e., "weight"), just skip the big block game and build a 6 ARC with a Proof CF barrel.

I have a 6 ARC build that I'll be doing next year. I can't decide between a 14.5 build and a 16 or 18 inch build considering that they both shoot well out to great distances, although the longere barrels will have more velocity and hitting power at farther distances. I'm using the UIC receiver set and handguard from ADM.

 

[Cascade Hemi]

Thank you so much for this review. I think I'll go with 308 then in the 16-inch Proof CF barrel. I also think I'll go with the VSeven, the reviews I've watched and read also mentioned the handguard/barrel nut design. I can't thank you enough. Beautiful rifles too!

Proof CF barrels aren't light weight, they are just lighter weight than the equivalent profile all steel barrel. There are plenty of lower weight steel options that aren't pencil barrels too. For example (ignoring button vs cut rifling) a Criterion Hybrid 16" with rifle gas is 2.5lb. The all steel barrel is more rigid, will have significantly less mirage, costs much less, and is available in rifle gas instead of intermediate. If you go rifle gas with an AGB you can run a low mass carrier and a 2oz buffer. You end up lighter weight, same/better performance, and a lot less cost.

 

[Hecouldgoalltheway]

Proof CF barrels aren't light weight, they are just lighter weight than the equivalent profile all steel barrel. There are plenty of lower weight steel options that aren't pencil barrels too. For example (ignoring button vs cut rifling) a Criterion Hybrid 16" with rifle gas is 2.5lb. The all steel barrel is more rigid, will have significantly less mirage, costs much less, and is available in rifle gas instead of intermediate. If you go rifle gas with an AGB you can run a low mass carrier and a 2oz buffer. You end up lighter weight, same/better performance, and a lot less cost.

Sure, but they don't look as cool, so..... yeah..

 

[MSTN]

I too am a big fan of Criterion barrels.

The Criterion Hybrid 16" does weigh just 5 ounces more than the Proof CF 16". That's a fair trade off for a $660 price delta. I'm confident that with match grade ammo the Criterion would not disappoint in the accuracy department. So, that's one excellent way to do such a build a tad cheaper.

I had no idea there was even such a thing as a 2 ounce buffer. But, I'm going for sub-MOA at 100, not the world's lightest gun that will cycle.

So, H2 for me, with LMOS JP BCG and SLR adjustable gas block. I've got eight years of use with my own combo, shown in photo #4, above. It now wears a different stock (BCM SOPMOD Mod 2), different scope (K18i), and HUXWRX Flow 762 Ti. Has yet to disappoint.

Who developed the very first intermediate length gas system? None other than Eugene Stoner, working for Knight's Armament, for the prototype SR-25K (16") .308.

 

[Cascade Hemi]

I too am a big fan of Criterion barrels.

The Criterion Hybrid 16" does weigh just 5 ounces more than the Proof CF 16". That's a fair trade off for a $660 price delta. I'm confident that with match grade ammo the Criterion would not disappoint in the accuracy department. So, that's one excellent way to do such a build a tad cheaper.

I have no idea there was even such a thing as a 2 ounce buffer. But, I'm going for sub-MOA at 100, not the world's lightest gun that will cycle.

So, H2 for me, with LMOS JP BCG and SLR adjustable gas block. I've got eight years of use with my own combo, shown in photo #4, above. It now wears a different stock (BCM SOPMOD Mod 2), different scope (K18i), and HUXWRX Flow 762 Ti. Has yet to disappoint.

Who developed the very first intermediate length gas system? None other than Eugene Stoner, working for Knight's Armament, for the prototype SR-25K (16") .308.

An AR-15 carbine buffer with aluminum weights weighs 1.7oz. Lower reciprocating mass feels pretty good, even at 100 yards.

I've spent quite a bit of time behind Proof barrels, they shoot nice but they have serious trade offs. I'd rather have an all steel barrel, all things being equal. And I would rather have less dwell, not more. Some 16" barrels do fine with mid length gas, and some eat your brass.