Ultralight Ultralight Rifles

[OneSkinnyHunter]

the Solo carrier is already "chopped". He's referring to using a standard bolt carrier.

Aww, gotcha thank you - not enough coffee today

 

[StupidLightweight]

Great minds and well, you know!View attachment 644474

Please explain more, sir. I need to do this!

 

[left hunter]

Well, I took it as you have already done it! It’s just a piece of carbon fiber tube I have had for a while epoxied onto a Clark custom guns barrel nut.

I really like using the Spartan bipod/tripod system so I need to figure out a good way to run one of there adapters on it

 

[PistolPete]

Wow, these NFA lowers and LPK's are insanely light. Just assembled one, 4.2 oz stripped, 6 oz with LPK (no grip/buffer tube). I also removed some material from the hammer/sear notch, but didn't want to go too slim, assuming the polymer will wear slightly, but got the trigger decent.

Add a Hogue grip, A2 buffer tube and Farrowtech and you have a ~12 oz complete (straight pull) lower. I also used a set screw to hold the rear takedown detent; it's easy with the polymer lower because the set screw taps itself when you screw it in; it's tight - feels secure.

I'm also considering a DIY straight pull upper; got the aluminum BCG from Outdoor Sports USA that weighs 5.9 oz ($100); you could cut that off and drop an oz or two, then mill out an Aero Precision slickside and be under the weight of the Solo 300, for about $180 in parts.

I know many of these parts are far from mil-spec, and probably wouldn't last very long, but I don't think I'll shoot this rifle 1000 times in my life, so...

 

[Thegman]

Wow, these NFA lowers and LPK's are insanely light. Just assembled one, 4.2 oz stripped, 6 oz with LPK (no grip/buffer tube). I also removed some material from the hammer/sear notch, but didn't want to go too slim, assuming the polymer will wear slightly, but got the trigger decent.

Add a Hogue grip, A2 buffer tube and Farrowtech and you have a ~12 oz complete (straight pull) lower. I also used a set screw to hold the rear takedown detent; it's easy with the polymer lower because the set screw taps itself when you screw it in; it's tight - feels secure.

I'm also considering a DIY straight pull upper; got the aluminum BCG from Outdoor Sports USA that weighs 5.9 oz ($100); you could cut that off and drop an oz or two, then mill out an Aero Precision slickside and be under the weight of the Solo 300, for about $180 in parts.

I know many of these parts are far from mil-spec, and probably wouldn't last very long, but I don't think I'll shoot this rifle 1000 times in my life, so...

How are you planning to add a bolt handle to the carrier? I've looked at pictures of those carriers but wasn't sure if there was enough material there to drill and tap for a handle. I'm curious about what solution you find, how easy it is and how well it works. Could be a good system if you can get that to work well.

 

[PistolPete]

How are you planning to add a bolt handle to the carrier? I've looked at pictures of those carriers but wasn't sure if there was enough material there to drill and tap for a handle. I'm curious about what solution you find, how easy it is and how well it works. Could be a good system if you can get that to work well.

That's definitely my concern as well. Plus with it being aluminum, only getting a few threads of engagement would tend to wallow out. Might not be worth the time and risk, only to save $100.

 

[StupidLightweight]

Well done, Pete! You have a solid blueprint for an ultralight blaster.

Below are photos of two carriers that are threaded for knobs. Hopefully this helps people out. The full-length one is a DSA aluminum carrier with left-side charge that I did myself; the chopped carrier is a steel version with right-hand charge that gunsmith Ned Christiansen did.

Unless you're an advanced hobbyist, I suggest you have a machinist/gunsmith do the work. The results will turn out better.

 

[Thegman]

Well done, Pete! You have a solid blueprint for an ultralight blaster.

Below are photos of two carriers that are threaded for knobs. Hopefully this helps people out. The full-length one is a DSA aluminum carrier with left-side charge that I did myself; the chopped carrier is a steel version with right-hand charge that gunsmith Ned Christiansen did.

Unless you're an advanced hobbyist, I suggest you have a machinist/gunsmith do the work. The results will turn out better.

It looks like it worked okay with your DSA? It's holding up well? Looks like the DSA side cutout might be similar in depth to PistolPete's carrier, so it might work fine(?).

Although more expensive, one advantage to using the Solo is the "detent key" that replaces the gas key with that system, which helps keep the bolt locked. Another advantage is the bolt carrier is designed specifically as a side charger with plenty of metal in the threaded portion. I'll post a pic of that carrier as it will explain that better.

 

[StupidLightweight]

It looks like it worked okay with your DSA? It's holding up well? Looks like the DSA side cutout might be similar in depth to PistolPete's carrier, so it might work fine(?).

Although more expensive, one advantage to using the Solo is the "detent key" that replaces the gas key with that system, which helps keep the bolt locked. Another advantage is the bolt carrier is designed specifically as a side charger with plenty of metal in the threaded portion. I'll post a pic of that carrier as it will explain that better.

Please post pics of the detent key. That sounds like a cool solution.

My DSA carrier is holding up fine, though I likely only have 100 rounds through it in 3 years. In its original .300 BLK pistol configuration, that little bugger kicks!

 

[BBob]

Please post pics of the detent key. That sounds like a cool solution.

 

[Thegman]

Here's the Solo carrier, bolt handle and "detent key". The bolt handle has about 4 3/4 turns of thread contact.

The ball detent actually locks into the round cutout in the upper where the gas tube normally comes through, not the cutout for the cam pin as I think I stated before.

 

[StupidLightweight]

I see now. Thanks for sharing, guys.

 

[passinggas33]

Sorry if I missed this, but has anybody built one of these in a 6ARC?

 

[StupidLightweight]

Yes, I've built a straight-pull AR in 6mm ARC. It's easy to do. You're in WA, where .224-caliber bullets are not legal for big-game, so that would be a good option. PM me and I'll send you an article I wrote. Be warned, however, that most people find the Grendel-based cartridges to be harder to cycle.

 

[BLJ]

Yes, I've built a straight-pull AR in 6mm ARC. It's easy to do. You're in WA, where .224-caliber bullets are not legal for big-game, so that would be a good option. PM me and I'll send you an article I wrote. Be warned, however, that most people find the Grendel-based cartridges to be harder to cycle.

I’d be interested in your experience with the 6 ARC as well.

 

[StupidLightweight]

I don't have a ton of experience with the 6mm ARC on game, so I can't help there. But I have built and shot a few 6mm ARCs. For big-game in states where the .223 isn't legal, bullets in the 95- to 108-grain range offer low recoil and superb ballistics. Here's a chart comparing the ARC against the gold-standard .223 with 77-grain Tipped MatchKing bullets.


Assuming a minimum speed of 1,800 fps for expansion, the 6mm bullet gets you another 75 yards or so of killing range. More importantly, it drifts less in the wind. The chief negative over a .223 is an increase in recoil, which ain't much.

Now, let's talk delivery system. The lightest option is a straight-pull AR, so if ultralight is your goal, that's the route to go. You could build a rifle in the low 3-pound range. Personally, I think a gas-operated AR in 6mm ARC makes more sense — for predator hunting especially — and without much effort, a sub-5-pound gun can be had.

Another option is a bolt-action like the Howa Mini. I don't know its weight, but for the money, that's the best value. Regardless of the firearm, chop the barrel at 16 inches and get a suppressor if you don't have one yet. You will have a lightweight, compact, and potent firearm for everything from home defense to long-range shooting. And as a hunting gun, the 6mm ARC is as adept at killing ground squirrels as it is moose.

 

[PistolPete]

Here's where I'm at with a 300 Blk gasser. Could cut a few more oz with a slickside upper and lighter brace. If I converted to a Solo 300 I could cut another 8 oz or so.

I went ahead and ordered a Solo...

 

[Hackleback]

I found some inexpensive thread protectors for the barrel end threads on Amazon. The more common ones are steel, but I was able to find aluminum with a bit of searching. Just note that the threads can be either 1/2" or 5/8" depending on the barrel. Another option to protect the threads is simply a couple wraps of e-tape. My current project is sitting at 3 lbs, 14 oz, no mag, with a scope.

Options for front sling attachment? I'm thinking either drill a hole in the carbon forearm tube or modify a gas block (cross drill a hole) where the gas tube attaches. Thoughts?

 

[Thegman]

I found some inexpensive thread protectors for the barrel end threads on Amazon. The more common ones are steel, but I was able to find aluminum with a bit of searching. Just note that the threads can be either 1/2" or 5/8" depending on the barrel. Another option to protect the threads is simply a couple wraps of e-tape. My current project is sitting at 3 lbs, 14 oz, no mag, with a scope.

Options for front sling attachment? I'm thinking either drill a hole in the carbon forearm tube or modify a gas block (cross drill a hole) where the gas tube attaches. Thoughts?

I think I'd opt for a couple of holes drilled in the CF tube with a loop of paracord run through, though I haven't done that yet, myself.

You can see this on a few of my pictures, but as a temporary work around I ran loop of paracord through a piece of bicycle inner tube to increase friction and put that around the handguard. With a sling on it chinches up and doesn't slip at all. My "temporary work around" has become not quite temporary enough as I'm still using it.

 

[PistolPete]

FYI: New Frontier has 30% off lowers and handguards (right after I ordered some from them). $25 polymer lowers!