Ultralight Ultralight Rifles

[robtattoo]

Been thinking about doing this with an A1/2 buffer tube. Haven't quite figured out how to make an ultralight yet strong butt plate for it yet. Still thinking...

What's the wall thickness on your CF tube? I was also wondering if I'd have enough strength if I had to sand it down further internally to get it to fit. Definitely post your results

Will do!
It's a 2mm sidewall, so there's plenty of meat to take off a half mil & more than strong enough.

I don't think you're going to beat a clamp on aluminum number, without spending a bunch of money.

I'll be milling a bunch off my plate too. There's a QD sling mount & bracing 'spine' running its length that I can live without. I can also remove the grippy surface & radius all the edges. Maybe drill a hole or two. I may end up gluing a thin flip flop on there for padding, if recoil gets too severe.

 

[robtattoo]

I'm really thinking that I can drop the billet upper to less weight than a standard cast.
The cast is 7.3oz, the billet is 10.4 & I'm literally taking half of it away. Once I figure out which scope I'm using & where it needs to be positioned, all the rail I'm not using is getting binned too.
By my estimations, I should end up at a complete bare rifle weight of 3lb 12oz.
If someone dies & leaves me the money for an aluminum BCG, I could drop that to 3lb 7oz.

 

[StupidLightweight]

I'm really thinking that I can drop the billet upper to less weight than a standard cast.
The cast is 7.3oz, the billet is 10.4 & I'm literally taking half of it away. Once I figure out which scope I'm using & where it needs to be positioned, all the rail I'm not using is getting binned too.
By my estimations, I should end up at a complete bare rifle weight of 3lb 12oz.
If someone dies & leaves me the money for an aluminum BCG, I could drop that to 3lb 7oz.

Well done. From a practical standpoint, you've gone far enough. Additional weight loss is purely for shits and giggles, which is a fine reason to keep whittling, but I'm of the belief that once you drop below the 4-pound weight, these flyweights become a handicap.

 

[robtattoo]

Well done. From a practical standpoint, you've gone far enough. Additional weight loss is purely for shits and giggles, which is a fine reason to keep whittling, but I'm of the belief that once you drop below the 4-pound weight, these flyweights become a handicap.

Thanks!
Yeah, by the time I'm scoped, I should be mid-4lb range & that's definitely light enough!

 

[Thegman]

Well done. From a practical standpoint, you've gone far enough. Additional weight loss is purely for shits and giggles, which is a fine reason to keep whittling, but I'm of the belief that once you drop below the 4-pound weight, these flyweights become a handicap.

Heresy!!!

 

[robtattoo]

Well, my carbon handguard & barrel nut won't be here until Friday, the carbon tube for my buffer/stock is getting delivered on Monday & I can't get in to the machine shop until the weekend, but other than that.......

 

[FullyTorqued]

Well, my carbon handguard & barrel nut won't be here until Friday, the carbon tube for my buffer/stock is getting delivered on Monday & I can't get in to the machine shop until the weekend, but other than that.......

View attachment 683623

How are you keeping that cutdown steel BCG locked forward and the bolt in battery without a spring or ball detent like on the Solo 300?

 

[robtattoo]

How are you keeping that cutdown steel BCG locked forward and the bolt in battery without a spring or ball detent like on the Solo 300?

I'm sure it's going to get bumped out of battery occasionally. I just need to be careful.
Right now, I've only mocked it up into one lump, but it feels like there's enough spring pressure between the hammer & back of the BCG cutout & the friction of the gas key in its rotation slot that it shouldn't be too much of an issue.
Once the barrel is tightened down, i think there should be a little extra friction between the locking lugs too.

 

[StupidLightweight]

Between magazine pressure and bolt friction, the BCG stays forward on standard uppers. It's likely not as secure as the SOLO 300 (haven't used one yet), but it works fine.

 

[robtattoo]

If anyone is interested, there are some 'Unbranded' poly lowers on Peacegeek.net right now for $25
They're actually NFA blems (New Frontier Armory, not tax-stampy nfa...) & weigh in at 3.2oz

If you've not dealt with them before, Peacegeek are awesome.

 

[StupidLightweight]

Thanks for sharing. That's a great price for the lower.

I've been on Peacegeek's site for 10 minutes now and found these 8.5-inch barrels without gas port for $29.95! For that price, it's worth buying just for a gimmick. Turn that puppy down, use an SBR lower, and you'll be close to sub 2 pounds.

8.5 inch barrel with ext -.223 Wylde

www.peacegeek.net

 

[Thegman]

If anyone is interested, there are some 'Unbranded' poly lowers on Peacegeek.net right now for $25
They're actually NFA blems (New Frontier Armory, not tax-stampy nfa...) & weigh in at 3.2oz

If you've not dealt with them before, Peacegeek are awesome.

You are the king of finding stuff...

Email says my aluminum bolt handle is in the mailbox. I'll check it out later today and thanks for the tip on that!

To add, is this the one?

UAR Carbon Series Lower

www.peacegeek.net

Where did you get the weight and other info on it?

 

[JBradley500]

Anyone get rid of the castle nut and end plate by putting a set screw through the circular recess in the lower and up into the buffer tube slot?... And maybe some loctite on the buffer tube threads?

 

[robtattoo]

You are the king of finding stuff...

Email says my aluminum bolt handle is in the mailbox. I'll check it out later today and thanks for the tip on that!

To add, is this the one?

UAR Carbon Series Lower

www.peacegeek.net

Where did you get the weight and other info on it?

I spend an awful lot of time mooching around a lot of different gun sites & have a few friends in the industry to ask about stuff
I reckon, if you're being really silly, you could chop the Ruger handle in half & still have plenty to get hold of.

That's the one, yes. A good friend of mine spends a lot of time researching stuff for the gun shop he works for. He spoke to Peacegeek to ask who made the lowers, then found a Tumblr thread about the NFA poly stuff & the weight is noted there.

Anyone get rid of the castle nut and end plate by putting a set screw through the circular recess in the lower and up into the buffer tube slot?... And maybe some loctite on the buffer tube threads?

How would you deal with the rear takedown pin detent? Just eliminate it?

 

[JBradley500]

I'm using an M4E1 lower so it's tapped for a setscrew anyway. The plate doesn't do anything other than keep the buffer tube from rotating.

 

[robtattoo]

I'm using an M4E1 lower so it's tapped for a setscrew anyway. The plate doesn't do anything other than keep the buffer tube from rotating.

Ahhh, I gotcha. In that case, I'd just use a set screw as you suggest. Half an ounce is half an ounce!

 

[PistolPete]

Anyone get rid of the castle nut and end plate by putting a set screw through the circular recess in the lower and up into the buffer tube slot?... And maybe some loctite on the buffer tube threads?

I did just that on my NFA. Drill the hole out to proper diameter maybe 1/4" deep and put a set screw behind the detent and spring. Screw self taps into the polymer!

 

[ChrisAU]

Thanks for sharing. That's a great price for the lower.

I've been on Peacegeek's site for 10 minutes now and found these 8.5-inch barrels without gas port for $29.95! For that price, it's worth buying just for a gimmick. Turn that puppy down, use an SBR lower, and you'll be close to sub 2 pounds.

8.5 inch barrel with ext -.223 Wylde

www.peacegeek.net

Dang that makes me want to build another one ha.

 

[ebrownw2]

Thanks for sharing. That's a great price for the lower.

I've been on Peacegeek's site for 10 minutes now and found these 8.5-inch barrels without gas port for $29.95! For that price, it's worth buying just for a gimmick. Turn that puppy down, use an SBR lower, and you'll be close to sub 2 pounds.

8.5 inch barrel with ext -.223 Wylde

www.peacegeek.net

And just like that this thread continues to coax money out of my wallet.

 

[ebrownw2]

I’ve got everything on order or here except the butt stocks. I want one fixed as light as possible and one folder. Or else just a folding adapter for the fixed stock.

The green mountain barrels are going to LRI to get turned down to a Faxon pencil profile. I may or may not have a spare or two when the dust settles.

Building one with a Faxon barrel as well for a more budget friendly build. (And to play with while waiting on the custom barrels Did we ever decide if it’d be ok to just leave the port open with a 7” hand guard? If not what is the preferred lightest gas block to reverse and will it fit in a kaw pcc hand guard?