Lightweight AR Builders Club

[DDadams]

Big weight savings to be had in optics choice. The SPARC is good and seems more robust than the Holosun. That being said the Holosun has been out long enough to prove itself and I think it’s up to the task. Added benefit of the change is having a motion activated red dot now.
View attachment 255329
View attachment 255330
Nearly 4 oz weight savings to be had here, cutting optic weight by 50%. So far I’m quite happy with this decision.

Which holosun is that?

I thought the AEMS was the best choice at 5.5 ounces but I guess I need to change it out to another rifle now.

 

[Squid556]

Which holosun is that?

I thought the AEMS was the best choice at 5.5 ounces but I guess I need to change it out to another rifle now.

I dug through Holosuns product list. Decided the 403 B was the right choice for me.

Here is their 403 series. Few different variations to choose from.

403-HOLOSUN

403 series optics get you in the door with a durable, lightweight 20mm red dot sight at an economical price. 403 series optics feature a 2MOA dot with 12 brightness settings, two which are NV-compatible. 403 series optics provide up to 100k hour battery life (403R), 6061 Aluminum Housing...

holosun.com

 

[Squid556]

Decided to finally take the plunge on a lightweight bolt carrier group. This is sold under the Right To Bear name but I suspect its made by Toolcraft.

RTB Complete Lightweight Bolt Carrier Group - Black Nitride

Our black nitride-finished bolt carrier group weighs just 8.9 oz., creates less reciprocating mass to reduce recoil and allows proper cycling with less gas.

www.righttobear.com

It was tempting to cut a lot of fat here. Keeping with the theme of the other parts on this build I decided to play it safe by staying in the 8-9 oz range. This rifle needs to stay reliable and strong, wasn't willing to sacrifice those qualities.


This BCG weighs in at 8.9 oz. Offering a 3 oz weight savings over my standard BCG. 3 oz is a pretty big deal when shaving weight I found.

After several mags of testing I found my combination to work very well.
-Midlength gas
-Standard block
-8.9 oz carrier
-3 oz standard carbine buffer
-Strike Ind. flat spring.

.223 ejecting at 3:00
5.56 ejecting at 2:00

Nitride finish has worn on a couple corners although I think that's unavoidable. Will keep testing this combination, so far so good.

 

[Squid556]

Thread Update: 14.5” Project Complete

Well after weeks of research and testing I’m happy with the final result. Started with an already handy ish 6 LB 9 OZ rifle.

After swapping red dot, upper, BCG, lower, and some lower parts… and a few hundred bucks…… I managed to drop another 3/4 LB (~12.5 oz) effectively pushing this rifle into a whole new category.

This thing is super handy and nimble! Only 5 LB 12 OZ fully kitted. It can be operated with one hand. I had a guy pick it up and wonder if it was an air rifle.

I don’t miss the forward assist and am starting to prefer the look without actually.

The 8.9 oz BCG with standard block, and standard carbine buffer arrangement has turned out to be perfectly gassed. It is soft shooting for what it is. That being said it’s taking some time to retrain my muscle memory as I tend to over handle the rifle past targets.

I’m very happy with the fit and finish of the 2A Armament lower. They removed meat where it was safe and left it where needed. Even comes with a bolt to adjust out any slop between the upper and lower.


The simplicity of the Holosun 403B is welcome change. I never have to remember to turn it on or off. The older Vortex had better glass quality but this will work just fine.

PM me if you want more details on the build, I kept it brief knowing this post would be quite long already.

Looking forward to continuing this process to my longer range build. As well as seeing INGOs handy carbines weight saving tricks.

 

[Squid556]

Adding some good places to research lightweight parts

Carbon Fiber Smoke Composites

Smoke Composites makes advanced carbon fiber AR, PCC and 308 components. Free-floating hand guards, butt stocks, and more. Lightest in the industry.

www.smokecomposites.com

Carbon Fiber AR-15 and AR-10 Accessories

Lightweight and durable guards, grips, and buttstocks for AR. Composite materials, usually reserved for space exploration, now for the firearms industry.

brigandarms.com

V Seven Weapon Systems

The Cure for the Common AR Ultra-light titanium and aluminum components for the AR-15/AR-10 and SCAR platforms Match grade barrels 5.56 and 300 AAC BLKOUT.

www.vsevenweaponsystems.com

2A Armament Products - 2A Warehouse

2awarehouse.com

5.56 Barrel | AR Barrels | Gun Manufacturers in Ohio

We have a variety of 5.56 NATO barrels and .223 Remington barrels to best fit your firearm and needs. Try out our gunner, Gov't, or pencil profiles.

faxonfirearms.com

 

[92FSTech]

Good thread! I've been considering putting together a minimalist upper (which inevitably will morph into a full rifle, lol) just for fun...not full-on ultralight, but cutting some of the obvious stuff and without a bunch of accessories hung off of it. Probably just a Romeo5 and a sling.

What is everybody's experience with pencil barrels? I've specifically been looking at the Faxon pencil-profile 14.5 with fixed, low-profile flash hider or brake. It avoids the need to pin and weld, and seems like a very significant weight savings, particularly out front where it really matters. I've had good experiences with Faxon in the past, but I'm also open to other brands if somebody has suggestions. My big hangup on the pencil barrel, though is that I got burned once before with a Mini-14 that wouldn't stay on an 8 1/2 x 11 sheet of paper at 100 yards due to barrel whip. I don't want to go down that road again. Clearly this isn't meant to be a precision build, but it's got to be at least somewhat accurate to be useful...say somewhere in the ballpark of 2-3 moa.

Has anybody put one of these barrels on paper at 100 yards and if so can you report results? Will it group? How quickly does it heat up, and when it does, how much does it open up? Does the group stay centered or drift around?

 

[Squid556]

Good thread! I've been considering putting together a minimalist upper (which inevitably will morph into a full rifle, lol) just for fun...not full-on ultralight, but cutting some of the obvious stuff and without a bunch of accessories hung off of it. Probably just a Romeo5 and a sling.

What is everybody's experience with pencil barrels? I've specifically been looking at the Faxon pencil-profile 14.5 with fixed, low-profile flash hider or brake. It avoids the need to pin and weld, and seems like a very significant weight savings, particularly out front where it really matters. I've had good experiences with Faxon in the past, but I'm also open to other brands if somebody has suggestions. My big hangup on the pencil barrel, though is that I got burned once before with a Mini-14 that wouldn't stay on an 8 1/2 x 11 sheet of paper at 100 yards due to barrel whip. I don't want to go down that road again. Clearly this isn't meant to be a precision build, but it's got to be at least somewhat accurate to be useful...say somewhere in the ballpark of 2-3 moa.

Has anybody put one of these barrels on paper at 100 yards and if so can you report results? Will it group? How quickly does it heat up, and when it does, how much does it open up? Does the group stay centered or drift around?

I haven’t tried the pencil, but Ian McCollum has some good documentation on what you’re asking about.

 

[92FSTech]

Yeah I've seen that. But I'd rather hear some independent feedback from people here who don't have any vested interest in selling a product.

 

[gsxr219]

Adding some good places to research lightweight parts

This thread has great info. Thanks for taking the time to put it all together

 

[DDadams]

Yeah I've seen that. But I'd rather hear some independent feedback from people here who don't have any vested interest in selling a product.

I can't dig it up now but others on reddit of all places got even better results on the faxon pencil barrels than Ian did.

I'd have no worries putting one on a future non-shtf build at this point personally. Especially with how good Faxon treats you if you have an issue.

 

[SmileDocHill]

I stopped by the Fostech booth at the nra show. Wow! They are out of Seymour Indiana. They have an aluminum alloy (stronger than aluminum) and a complete AR thats under 5 pounds. 4.7 if I remember correctly. It feels amazing.
I didn't have the funds to get a complete rifle but bought their lightweight rail, bcg, and muzzle device.

 

[BoilerWes]

I stopped by the Fostech booth at the nra show. Wow! They are out of Seymour Indiana. They have an aluminum alloy (stronger than aluminum) and a complete AR thats under 5 pounds. 4.7 if I remember correctly. It feels amazing.
I didn't have the funds to get a complete rifle but bought their lightweight rail, bcg, and muzzle device.

Let us know how it performs! Checked out their website and they have some nice looking products.

 

[DDadams]

Fostechs new magnesium alloy parts are a HUGE improvement over the last generation "lightweight" parts they had.

The last stuff was just lightening cuts + whole sections skeletonized and it was STILL heavier than a standard Aero set. Now it's actually lightweight.

They're using the same alloy that Roam uses for their AR10s

Roam is coming out with AR15's this year hopefully too though. They're going to be the undisputed king of lightweight sets with the non-FA upper set. It should be under 10 ounces for both pieces.

I think there's polymer / hybrid material sets that are in the 8-9 range but I'd rather have all metal - even if it is a magnesium alloy.

But for me, I'll stick to 2A Armaments 7075 and V Sevens 2099 Lithium/aluminum instead. I don't like how easily magnesium is to chip and break. Even in mixed alloy form. That and it's extremely prone to rust once the tagnite coating wears off.

 

[d.kaufman]

I stopped by the Fostech booth at the nra show. Wow! They are out of Seymour Indiana. They have an aluminum alloy (stronger than aluminum) and a complete AR thats under 5 pounds. 4.7 if I remember correctly. It feels amazing.
I didn't have the funds to get a complete rifle but bought their lightweight rail, bcg, and muzzle device.

I picked up their 13" mach 2 at the
show myself. Believe it weighs just over 5oz including barrel nut

 

[BigRed3588]

Yeah I've seen that. But I'd rather hear some independent feedback from people here who don't have any vested interest in selling a product.

I have Faxon pencil barrels on two of my rifles and I’d absolutely recommend them. One is on a fairly recent build and I’ve only tested it for function but I sighted in the other on a 100 yard indoor range. I didn’t take measurements but you should easily be able to hold 2-3 moa groups with it. I’d say it was every bit as accurate as my DDV7. They’re 4150 steel so they don’t heat up quickly either.

 

[BoilerWes]

Fostechs new magnesium alloy parts are a HUGE improvement over the last generation "lightweight" parts they had.

The last stuff was just lightening cuts + whole sections skeletonized and it was STILL heavier than a standard Aero set. Now it's actually lightweight.

They're using the same alloy that Roam uses for their AR10s

Roam is coming out with AR15's this year hopefully too though. They're going to be the undisputed king of lightweight sets with the non-FA upper set. It should be under 10 ounces for both pieces.

I think there's polymer / hybrid material sets that are in the 8-9 range but I'd rather have all metal - even if it is a magnesium alloy.

But for me, I'll stick to 2A Armaments 7075 and V Sevens 2099 Lithium/aluminum instead. I don't like how easily magnesium is to chip and break. Even in mixed alloy form. That and it's extremely prone to rust once the tagnite coating wears off.

I have been really happy with my 2a purchases. Anyone know when they will be back online?

Probably going to try a Vseven build this time around. I’ve have read reviews of the alloy chipping on their hand guards. Should I stay away from those? I usually prefer to match manufacturers of the handguard with the receiver set when building.

 

[DDadams]

I have been really happy with my 2a purchases. Anyone know when they will be back online?

Probably going to try a Vseven build this time around. I’ve have read reviews of the alloy chipping on their hand guards. Should I stay away from those? I usually prefer to match manufacturers of the handguard with the receiver set when building.

Anything magnesium blended can chip easily.

I think MrGunsAndGear or whatever his name is on YT had one of the magnesium handguards from them and he dropped his gun and if took like a 1.5" chunk out of it and he was saying something like "see that isn't even that bad it still works" - I'd prefer a material a bit heavier that doesn't do that if dropped personally.