So I'm looking to put together a lightweight large frame AR for hog and coyote hunting with a thermal. I've been eyeing a Christensen Arms ca-10g2 which come in at 7.2 lbs without an optic. Is it possible to build something that light or is it something they've mastered? I have an Aero upper and lower that I can free up and was thinking of putting something together. Was thinking a Proof 22 inch barrel with some other lightweight components. Looks like some companies are making some carbon fiber handguards also. Anyone ever put something together like this and what components did you use? Would like to have an adjustable gas block so I can run suppressed
- Thread starter giannid
- Start date
Built mine out a few years ago. Goal was to get under 7 lbs but it ended up being a couple ounces over. At the time the lightest receivers were 2A arms and F1. I used the F1 and my buddy built out his with 2A. I used a 16 inch Faxon gunner lite. Midwest handguard. I’ve been very happy with mine, holds MOA out to 400. Buddy wasn’t as happy with his and switched to a Proof 20in barrel which helped. Calvin Elite triggers on both.
I've been doing research to do the same thing. Target of 7lbs or so. Here's one good article I found. https://www.shootingillustrated.com/content/building-a-lightweight-ar-10-on-a-budget/ I've been using it as a baseline for component weights. When I find a part I like I compare the weight to the article. Often I'm disappointed, but soon I should have my parts list together.
One thing I don't know is what the trades off are for a light weight bolt. Don't want to give up any accuracy.
One thing I don't know is what the trades off are for a light weight bolt. Don't want to give up any accuracy.
Commenting to keep track of this thread, I have a similar interest.
The receivers, barrel, bcg, optic and mounting, handguard and stock are all major elements to AR weight.
A set of 2A Arms Xanthos receivers and handguard, or the Smoke composites handguard, a titanium or JP LMOS bcg, pencil profile steel barrel, Smoke or EFT(?) stock, and a shirt barrel will keep the weight down. You could make an AR-10 with no optics or ammo that’s about 6 pounds or a hair over if you picked all the right parts.
A set of 2A Arms Xanthos receivers and handguard, or the Smoke composites handguard, a titanium or JP LMOS bcg, pencil profile steel barrel, Smoke or EFT(?) stock, and a shirt barrel will keep the weight down. You could make an AR-10 with no optics or ammo that’s about 6 pounds or a hair over if you picked all the right parts.
I'd probably be happy with something under 8 pounds. I'd rather have something that runs like a sewing machine than something light and finicky. Thinking of using an aero upper and lower, standard area bcg, jp high pressure bolt, slr adjustable gas block, smoke handguard, and proof barrel with adapter for can. Not sure if that's going to put me under 8 pounds but I hope it would. Looking for someone that's built something similar. The Christensen Arms ca-10g2 comes in at 7.2 pounds with a 22 inch barrel. Might go that route if I can't build one as light as they do.
I had initially planned to build a lightweight 6.5 Creedmoor, but I found cutting weight gets exponentially more expensive the lighter you want to go. As I planned my build out, I found that it would have cost me roughly twice as much to get a 6.5 Creedmoor to be even remotely close to my basic bitch 6.5 Grendel. I figured at that point it wasn't worth the cost, when my Grendel already weighed in at ~8lbs and already has an effective range of ~400 yards. I'm not planning on shooting coyotes beyond that range, so a lightweight large frame build felt a little redundant.
When I came to that realization, I pivoted my Aero M5 build to be more of a stationary/target rifle and adapted my goals. After some tweaks, I settled in with it at around 12~13 lbs and it manages recoil like a champ. I'm not planning on hiking through the mountains with it, but it's accurate as hell and I can shoot it all day without fatigue.
It turns out going superlight on a large frame AR wasn't worth it for me, but if you have the budget for it, by all means go for it! The biggest bang for buck areas to save weight are the barrel and handguard, with the optic choice being another big variable. Just be sure to get the longest gas system you can find - especially if you go lightweight on the bolt carrier. Good luck!
When I came to that realization, I pivoted my Aero M5 build to be more of a stationary/target rifle and adapted my goals. After some tweaks, I settled in with it at around 12~13 lbs and it manages recoil like a champ. I'm not planning on hiking through the mountains with it, but it's accurate as hell and I can shoot it all day without fatigue.
It turns out going superlight on a large frame AR wasn't worth it for me, but if you have the budget for it, by all means go for it! The biggest bang for buck areas to save weight are the barrel and handguard, with the optic choice being another big variable. Just be sure to get the longest gas system you can find - especially if you go lightweight on the bolt carrier. Good luck!
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Compare the weights of those parts to the ones in the link I posted. Then you'll know.
I’m a 2A armament fan, I built a 308 that came at around 6.5 pounds with the xanthos receiver upper and rail with a full mass bag, and it’s still a strong rifle, your barrel would be heavier but you can easily get it in the 6+ pound range.
Having had my share of large frames.
No way you'll get the weight down using a standard BCG.
You can run anything else.....but the BCG is a heavy ass bitch.
No way you'll get the weight down using a standard BCG.
You can run anything else.....but the BCG is a heavy ass bitch.
That’s surprisingly light without using the 2A lower receiver and a lightweight BCG.
Interesting idea.
Im finalizing an LMT build in 308 using a Proof CF and almost pulled the trigger on a 22” 6.5
Proof barrel but decided I really want a 14.5 or 16” 6.5 instead. Been asking Proof to make either size in CF. We need to keep asking!
Im finalizing an LMT build in 308 using a Proof CF and almost pulled the trigger on a 22” 6.5
Proof barrel but decided I really want a 14.5 or 16” 6.5 instead. Been asking Proof to make either size in CF. We need to keep asking!
It was the 2A lower upper(the 2a xanthos series) and handguard, they are incredibly lightweight while still being structurally sound. I do use the full mass carrier, but my goal was to build a 308 that was the same relative weight as a average ar15, thankfully the 2a parts, titanium pivot and takedown, titanium brake, mft stock, titanium grip screw, and a heavy fluted barrel did the trick without having to get a lightweight bcg.
Seven? F4 Defense? I'm interested in building something similar.
6.9# without having to source anything, just order. https://www.roamrifles.com/shop/rifles/r-10-walhalla/
How much lighter are the 2a upper and receivers versus an Aero? I can't imagine they can shave that much weight off those parts being a DPMS pattern.
Half a pound. 24oz vs 16oz.
Can you weigh in on Small Frame vs Large Frame - any practical rigidity or overall strength differences? Assuming getting a 260 or 308 to run is just a matter of tuning the gas? I like the idea of a small-frame...
I don't understand your question. Small frame fits intermediate calibers like 6ARC, 6.5Grendel, 5.56 NATO. Large frame fits full rifle calibers like .308, 6.5CM. A lightweight AR-10 is about the lightest hunting gun you can get, besides very unique bolt actions like the Kimber Montana. A full rifle caliber can be an Elk round to 500-700yds or so with the best cartridges available. An intermediate caliber can be good on Deer to 500'ish or Elk to 300'ish. A heavier receiver can be more rigid and I'd prefer it if I was trusting my life to it vs having ultra-thin sections throughought the receivers.
The heavier your operating system and buffer spring is, the wider the range of operability it will have. An ultralight operating system like I have in mine is more picky but surprisingly hasn't been hard to tune. I have an adjustable gas block and adjustable BCG, and I just turned the BCG to full open and tuned the gas block. It's got a titanium carrier and a JP SCS H buffer in it, which I consider to also have a slightly soft spring for an AR-10. It runs great with the ammo I put through it, from 147gr FMJ, 155 Hornady and 180gr Black Hills. Precision with a Proof barrel was good, but I need to do more load testing to see which ammo mine likes. A heavier gun will always be easier to shoot.
Sorry, I meant a small-frame set that is meant to fire a creed or 308 sized case. F4 defense, POF Rogue, etc. A little less weight, a little smaller size, and the compatibility. Looking to build a 25 Creed for 131 Blackjacks.
About a half pound as upsidediwn stated, then another 5 ounces less using the xanthos handguard. Doing a lightweight build your really just chasing ounces everywhere but they add up. I think the 2A lightweight parts are strong from my experience, I tried a Odin works lighter handguard but I could literally see and feel it flex on a bipod, the 2A handguard and upper and lower seems very solid. The biggest weight savers for me were the upper, lower, handguard, titanium gas block, titanium brake, fluted barrel, and the mft stock.I used a few other titanium parts(pivot takedown pins, grip screw) but just because they weren’t cost prohibitive and saved a little weight.
Those are very unique guns that have big compatibility issues. I personally have no interest in an AR'ish gun that isn't compatible with AR parts, but if the as-built guns fit your use then they're an option.
Get a supporter tab if you want to sell. Do it again and you are banned.
Literally just posting to say I loved your forum username. No idea what this thread is about, haven’t read a word in it, but this user name -awesome.
Th
Thanks Bud!
I did this.
Aero M5E1 upper and handgaurd
FAXON 6.5 16" big gunner barrel
JP detent adjustable gas block
JP LMOS carrier and HP bolt
Aero carbine buffer lower
Radian raptor Lt charging handle
JP SCS
Magpul SL stock and K grip
Geissele G2S.
I ended up a little over 7lbs dry no optic. If you use a regular M5 upper/handgaurd rather than the E1 upper and handgaurd it will save another 1/2 lb. A SLR sentry 7 detent block will also save a little weight over the JP AGB
Runs pretty well after dialing in gas, doesnt shoot as great as I want it to but is is making good groups with good ammo, hovering over MOA consistently and I've shot it to 650yds successfully.
Aero M5E1 upper and handgaurd
FAXON 6.5 16" big gunner barrel
JP detent adjustable gas block
JP LMOS carrier and HP bolt
Aero carbine buffer lower
Radian raptor Lt charging handle
JP SCS
Magpul SL stock and K grip
Geissele G2S.
I ended up a little over 7lbs dry no optic. If you use a regular M5 upper/handgaurd rather than the E1 upper and handgaurd it will save another 1/2 lb. A SLR sentry 7 detent block will also save a little weight over the JP AGB
Runs pretty well after dialing in gas, doesnt shoot as great as I want it to but is is making good groups with good ammo, hovering over MOA consistently and I've shot it to 650yds successfully.
I can contribute in a small way to this thread. Sorta
I built myself a WWSD clone last year. The Faxon 15" carbon fiber handguard is nice. Seems light. Seems rigid. NOT cheap tho
...but... don't know if it'll work for a large frame AR build
I'm a cyclist so am a sucker for carbon fiber.
M
I built myself a WWSD clone last year. The Faxon 15" carbon fiber handguard is nice. Seems light. Seems rigid. NOT cheap tho
...but... don't know if it'll work for a large frame AR build
I'm a cyclist so am a sucker for carbon fiber.
M
How much did this set up cost you without the can and scope?
