ULTRA-LIGHT AR-15 - Readyman Store

ULTRA-LIGHT AR-15

My SHTF Gun, finally

by Jason Ross

We begin with a tale of two survival moments.

ReadyMan Challenge 1. Mike Simpson, contestant and extraordinary ReadyMan, climbs a brush-covered mountainside in a survival challenge where he is being tested to see how many calories he could collect in 36 hours. His fifty pound bugout bag on his back makes the ascent difficult, but his eight-pound AR-15 is the straw that breaks the camel’s back. He slings his AR, locking it into his pack. Less than ten minutes later, a giant tom turkey waddles out in front of him. Mike scrambles for his AR, but the turkey moves faster. The game is lost, right there and then — all because his rifle weighed a few pounds too much.

Not five miles away, I picked my way across a razor-sharp mountaintop hunting Blue Grouse. I carried my Benelli M4 at the ready, knowing that when a grouse flushed, it’d be over in a mili-second. Sure enough, forty-five minutes later, just when I was thinking about slinging my shotgun, two grouse flushed over the 3,000 foot drop.  In a flash, I popped them both and they fell just a bit downslope of where I stood. That would be dinner.

If I had a dollar for every time a game animal appeared the moment after everyone slung their guns or set them down…

Flashback three years, at Frontsight Nevada, “Practical Rifle Course.” Our instructor, Kevin Cress (saltiest Marine you’ve ever seen) invited everyone to “live with their ARs" by keeping them on their person during the entire four day course. After two days, ninety percent of the students were racking their ARs every chance they got. Turns out, “living with” an awkward chunk of eight-pound sharpness isn’t as sexy as it looks on TV.

All of this set me on a mission — a mission to engineer an AR not much heavier than a handgun.

As an imagineer of the coming apocalypse, I figure that firefights would be as rare and unexpected as UFO sightings. But, if and when they happen, they would come at the worst possible moment and with very high stakes. We would all be sitting around, completely absorbed in improvements to our backyard whiskey still, and then all hell would break loose. 

Most guys’ first thought would be, “Now where did I leave that assault rifle?”

If he’s trekking overland, just about any guy would sling his AR within the first fifteen minutes. Because trekking overland, if you’ve done your share, is a dirty bitch. Holding something in your hands, or even slung over your shoulder, feels like hiking with pebbles in your boots. No matter how big of a badass survivalist you are, like Mike Simpson, you will put that ever-loving rifle away.

The sum-total of this mishmash of logical tidbits amounted to this: I wanted an AR that felt like a child’s toy. I wanted a shit-ton of long-distance killing power in a teeny package. Preferably something I could wear on my back while I gardened and distilled whiskey. 

I know that I’m not disciplined enough to “live with” something sharp and heavy around my neck, sixteen hours a day, seven days a week. But, if it weighed four pounds soaking wet, then there’s a good chance I could guilt myself into doing the right thing. 

I figure that the gun I have very close-at-hand is better than any other gun. While I’d rather be trekking with a .308 that’ll take down an elk and blow holes in full-size pine trees, I know that a nine-pounder like that will be stowed in my backpack, not in my hands where I’ll need it to fight.

You get the picture. Here’s what I learned in two years of building and testing ultra-light AR-15s.

  1. It can be done. Yes, you can build a sub-four-pound AR-15 and it’s AWESOME! It feels weird and exhilarating to blast the hell out of a 200 yard target with something that hefts like your kid’s BB gun. On the other hand, you gotta be rich as Croesus to get it under four pounds. The components are WAY expensive.
  2. You CAN build a five-pound AR-15 for under $700!! And, a five-pound AR-15 is just about as jaw-dropping as a 3.75 pound AR-15 that costs as much as your wife’s boob job. (I’m not going to opine on which to purchase if you find yourself in that conundrum.)
  3. There’s a lot of trial-and-error that goes into packing that much power into an ultra-light frame. I’ll give you the details below, if you’re serious about dropping down this rabbit hole.

Bottom line: I have three AR-15s that I could wear slung on my back while I work around the ranch. They’re not nearly as tough as a Sig Sauer AR-15 (weighing over 8 pounds), but they would be strapped to my back on a two-point sling every single minute of every single day in a grid-down world. Plus, my wife and kids could shoot them without cringing at the recoil or drooping because of the weight. 

The ultra-light AR-15 is a minor miracle with fewer trade-offs than I originally suspected.

If you’re a tinkerer — and I suspect you are — I offer you this as a project that will give you hours of pleasure both on the range and on the workbench. 

Plus, your buddies will be very impressed.

P.S. Email me, or post on the ReadyMan Community Board, and let me know about the new stuff you innovate and discover as you play with the ultralight concept.

 

EXPENSIVE ULTRA-LIGHT (about 3 pounds 14 oz.) approx. $3,000

[cheap version further below]:

Here’s our current Ultra-light set-up. This will improve, but we had to release the video at some damn point.

1.  Short pencil barrel. Yankee Hill. This saves weight (about eight ounces off of the normal M4 light barrel.) It also causes loads of headache:

  • BATF Form One. A 10.5 inch barrel needs to be registered as an SBR (short-barreled rifle.) You must pay $200 (assuming you live in a gun-friendly state) and wait for six months to get approval to assemble your parts. You need to measure it, somehow, without assembling it before sending in the Form One.
  • Variation in gas pressure. A shorter barrel changes the amount of gas being pulled off to run your bolt. You’re going to want to add an adjustable gas block to tune the amount of gas hitting your bolt. Plus, an adjustable gas block will compensate for a lighter bolt carrier group.
  • If you don’t live in a gun-friendly state, then look at these VERY LIGHT 16 inch barrels from Faxon Firearms (1.19 pounds!)

2.  Light upper/lower receiver. Our choice is the 2A Armament Balios.

3. Bolt Carrier Group. Our preference varies. The lightest BCG (Boom-fab Titane) creates dependability issues when dirty.  We think these issues can be largely fixed with fine-tuning. Our most-tested (but four ounces heavier) light BCG was the Spike’s Tactical. We’re currently testing a variety of others, all from VertexOps.com.

4. Trigger Group. We’re not thinking about weight on this. We want a bad-ass trigger break. Geissele

5. Adjustable Gas Block. 650 Gas Block. Check out our tests.  

6. Shoulder Stock. Smoke Composite Open Shoulder Stock. Be patient ordering with Smoke Composite. It’s like one guy in the machine shop making the best product around. He’s slow to answer the phone/email because he’s a grease monkey like you and me.  (And, when you DO get him on the phone, he’s great to work with.) 

7. Hand Guard. Smoke Composite Mid Length Hand Guard. Don’t go with the Carbine Hand Guard or you’ll burn your leg on the gas block and compensator.  

8. Grip. Mag-pul MOE-K Grip

9. Sight Riser. (Trijicon RMR only) You should raise your sight up or you end up “scrunching” your head down to sight, which wastes time. 

10. Sight. Trijicon RMR. NOT bomb-proof, but you can’t beat the weight.  

11. Compensator. 2A T3 Titanium Comp. Honestly, we haven’t tested many of these (two, actually) so we don’t know for sure if this is the best bet. It does allow a little carbon to hit your face on a short barrel. It’s light, tho.  

12.  Kibbles and Bits. You can buy light pins and what-have-you, but they’re not going to make a huge difference.  VertexOps is the place for most of this stuff.  

 

CHEAP ULTRA-LIGHT (about 5 pounds) under $1,000

Here’s our quick-and-dirty, no messing with the ATF, ultra-light design.

1. Bushmaster Carbon 15 Superlight ORC. (You should be able to find a better deal than their website shows. I bought mine for $700. Make sure you get the aluminum upper receiver because the carbon, i.e. plastic, upper receiver has problems. I broke two.) Make sure you get the pencil barrel and it’ll be 16 inch, which isn’t THAT much heavier than our ATF-tracked 10.5 incher.  

Franken-Gun Option: if you want to assemble your own gun, you can start with the New Frontier Armory polymer lower and buttstock. Then, you have to cobble together a bunch of other stuff (barrel, etc.) plus the trigger in the NFA is a POS, (but it’s LIGHT!) And, this lower is CHEAP ($140) and you can drive the price down — WAY down — by assembling your own gun from parts.  

2. Shoulder Stock.  Mission First Tactical. ($60) 

3. Adjustable Gas Block. We didn’t test a cheap one of these. But, you do need one, because when you cut this much weight, felt recoil will go up. Let us know what good options you find on-the-cheap.

4. Fore-grip. Sorry. No cheap option here, unless you Dremel the daylights out of your stock fore-grip. Smoke Composite Mid Length Hand Guard. Don’t go with the Carbine Hand Guard or you’ll burn your leg on the gas block and compensator.  

5.  Sight. Bushnell TRS-25. ($100) The riser is too heavy, but you could lighten it with a mill (if you have one of those laying around.) You could do the same with a drill and some elbow grease.  

6. Flash Hider. Get rid of it and get a thread protector. It’ll drop weight and look not-nearly-as-cool. 

7. Bolt Carrier Group. Just live with the stock Bushmaster bolt. OR spend some $$ and buy a Spike’s Tactical Light Weight. ($220) We’re not sure this is the BEST option (weight to $$ ratio), but we have tested the shit out of it. 

 

JASON’S SUPER-SECRET-SQUIRREL AR-15 MODIFICATION

(for your eyes only)

Most guys shoot their ARs wrong. They shoulder the stock like a normal scoped rifle, which is too low for an AR-15. This places the sighting line too low, which forces the shooter to gooseneck down and lean into the stock. That motion costs time and makes it impossible to achieve a natural point-of-aim. 

Ideally, you’d shoulder your AR and instantly be looking right through your sight without changing your head posture at all. If you could achieve that natural sight picture, then you will be able to “instinct shoot” accurately even before getting your sight aligned. Those saved tenths of a second can mean the difference of getting the first hits in a gunfight. It’s a big deal.

 With this in mind, I developed a registration point for regular guys to achieve Special Forces proper AR shouldering. With hundreds of thousands of rounds of training, the SOF guys learn this the hard way. I came up with a hack that’d make it easy for regular shooters to master the proper shouldering of an AR.

I took a stress-relief egg and sheared it in half with a hot knife

I drilled two holes in the VERY BOTTOM of my buttstock. This part is critical. You want the egg as low as possible on the stock so that you will shoulder the stock very high on your shoulder. The two holes are stacked vertically and they’re about an inch apart. I went 5/16” because I was going to use 1/4-20 screws, nuts and washers.

Then, I “drilled” out two holes in the half-egg with the back end of a red-hot drill bit, heated with a small propane torch. The hot drill went right through the egg. 

Then, I took a larger-size drill bit and did the same thing, going only half way down from the curved side of the half-egg. This created a relief hole so that the button-head screw was buried in the egg and wouldn’t hit my shoulder when the egg compressed. Make sure this relief hole is smaller than the washer you’ll be using so that the washer has to be manipulated to fit down the relief hole. You want as much “meat” beneath that washer as possible so that it doesn’t work its way through the rubber egg.

After, I attached the egg, making sure to bury the button-head of the screw, along with a washer, deep in the egg and I used a ny-lock nut on the backside. 

You can blacken the egg with a Sharpie or spray paint it. It’ll never look “tech,” but it’s a killer advantage. Not only does it fix the shoulder registration problem, but it reduces felt recoil by a lot.

Ultimate AR-15 Geek-out Weight Sheet

(Thanks, Maryland AR Shooters Group)


Evan Hafer
Evan Hafer

Author



4 Responses

Heather
Heather

April 16, 2016

I just built completed my build and am at 5.2..im a 5’4 fem who wanted something I would get bored shooting before I got tired. I used a lower from Tennessee Arms (great ppl to deal with) even had it engraved! I used a bcm key mod full length that was pricey but super light and looks awesome .. On a DD 16in chrome lined barrel .. Some other things but I love my rifle !

Brady
Brady

March 09, 2016

Good Article, I’m building my own lightweight carbine and with a 14.5 barrel I’m under 2k and under 50 oz! 48.25 is what my spreadsheet indicates. I love reading about other lightweight builds. They give me more ideas for practical weight savings.

mike
mike

January 22, 2016

you don’t have a picture of your stress egg concoction? I read that part a few times and still have no idea what the end result would look like or what you are really talking about…

Adam
Adam

January 07, 2016

For a good adjustable gas block that doesn’t break the bank check out Battle Tested Equipment. I ordered one yesterday after talking to Black Hole Weaponry about ordering a custom barrel.

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