No holds barred lightweight build

[BigBluePup]

Hey everyone.

So this is my first 6.5 build and you guys seem to be the best online resource for the Grendel so here we go...

The point of this build is pretty much summed up in the title, I want the lightest 6.5 humanly possible.
The reason you ask, I have some long range guns (custom Remington 700 Sendero .300RUM) and they are heavy pigs. Which is fine for hunting in the desert (we go to Wyoming every year for mule deer) and you're not climbing over stumps and brush and fences all the time like you do up here in the Pac NW.
So the goal is to make a feather weight mid range gun and the 6.5 fits the bill pretty well.


Being a non AR expert I want to get some opinions on where I can trim some weight.

so far this is what I have for parts. (non purchased yet)

Proof research 20" carbon fiber barrel and matching bolt,
Rainier arms forged upper without forward assist,
Sand hill titanium switch block,
Carbon fiber hand guard, (probably a lancer or whatever else might be lighter)
Bushmaster carbon 15 lower (I know I'm gunna catch flack for this but I think the new ones are a lot better then they used to be)
Sure fire suppressor and muzzle break,
Stock... I'm open to this, I have a good friend and hunting buddy of mine that is a metal fabricator (and probably the best tig welder on the west coast) and we've been playing with the idea of building a titanium or aluminum stock and seeing if we can save some weight and gain a little on the cool factor.
Optics will more then likely be Vortex or Night force,
I also want to do some iron sights on a 45* for quick target acquisition in the brush.

Anyone know where I can trim some weight?
I've heard of a company that makes a polymer internals kit to shave some weight anyone have more info on this?
This is all in spit wad status right now and once I get everything dialed I'll pull the trigger on the barrel and suppressor since they are the two big ticket items.

Thanks for the help in advance guys I'll take any criticism or help you guys have.

[stokesrj]

Here is my light weight rig, I wouldn't want it any lighter. http://www.65grendel.com/forum/showt...ll=1#post37482
Bob

[BigBluePup]

Why wouldn't you want to go lighter?

I'm thinking I drop a little weight on ya from the barrel, Lower, upper (no forward assist), and maybe stock depending on what we come up with, but I will gain some on optics.
How happy have you been with performance so far?
Do you have any light weight internals on it? and what milling on the bolt was done?

Thanks for the .02!

[kamrr4437]

Your right the only thing i wouldnt recommend is the lower. I would stick with a regular aluminum lower. Theres really no weight there anyway.

[melensdad]

Of the nearly 100 ARs that I've been involved in building, this gun that I built for my daughter was by far the lightest. It uses a pencil thin barrel and a full polymer Cavalry Arms lower. The Cav Arms lower integrates the lower, handgrip and buttstock into one, very lightweight, monolithic unit that saves weight by eliminating many of the bolts and other parts needed to hold separate comonents together. Its also very strong and takes abuse (think Glock). While this gun is built in 5.56, it could easily be done in 6.5 Grendel (and obviously it would not be required to be pink!). You could shave another 1 or 2 ounces by utilizing a different gas block that doesn't include a front sight.

[leopard6.5]

BigBluePup: I think Bob has you on the weight of his barrel. That 16" ( actually 14.5" plus an integral flashhider) Satern Spartan double fluted barrel weighs in at 1.1lbs..

The lightest weight Proof Research lists for any of their barrels is 1.5lbs.

I also have a Grendel rifle using the 16" Satern Spartan barrel( I also have one of their 18" Satern Spartan barrels on another rifle).
My total rifle came in at just under 5lbs.

I can't speak for Bob but personally I wouldn't want to go lighter than the 5lbs. because I start feeling an increase in recoil from a lack of weight to offset it.

I personally love that rifle with the 16" Satern Spartan barrel because it is so handy and everything I shoot with it just dies.

Welcome to the Horde and good luck with your build.

Lee

PS- I used an ACE ARFX buttstock and a Hogue overmolded handguard on that rifle. The ACE buttstock is very light and the Hogue handguard has the rubber overmolding which helps insulate my hands from the cold when I'm using it up north.

[LRRPF52]

I was also going to recommend the Corbon15 (now Bushmaster-owned) lower. They are pretty tough, and lighter than aluminum. You could also use the new FAB Defense stock with an internal recoil spring assembly to help mitigate that if you're concerned about it.

[BigBluePup]

BigBluePup: I think Bob has you on the weight of his barrel. That 16" ( actually 14.5" plus an integral flashhider) Satern Spartan double fluted barrel weighs in at 1.1lbs..

The lightest weight Proof Research lists for any of their barrels is 1.5lbs.

I also have a Grendel rifle using the 16" Satern Spartan barrel( I also have one of their 18" Satern Spartan barrels on another rifle).
My total rifle came in at just under 5lbs.

I can't speak for Bob but personally I wouldn't want to go lighter than the 5lbs. because I start feeling an increase in recoil from a lack of weight to offset it.

I personally love that rifle with the 16" Satern Spartan barrel because it is so handy and everything I shoot with it just dies.

Welcome to the Horde and good luck with your build.

Lee

PS- I used an ACE ARFX buttstock and a Hogue overmolded handguard on that rifle. The ACE buttstock is very light and the Hogue handguard has the rubber overmolding which helps insulate my hands from the cold when I'm using it up north.

Wow that is a pretty light weight barrel,
What is their (if they make one) weight in a 20" ?
From what proof is telling me the barrel and bolt combo weighs in at 2.4lbs
I don't want to run anything shorter then a 20".

Does anyone have the weight of a stripped Corbon15 lower compared to a aluminum lower?
as far as being to light weight, I'm not really worried about it. With it suppressed and integrated muzzle break the recoil won't be to bad.
I shoot a .50 desert eagle, .454 casull, and a .300RUM I like recoil lol

[BigBluePup]

I've looked into some of the Cav arms stuff but they are out of business now though from what I understand so finding their stuff might be tough.
I also like the idea of having an adjustable stock as well.

@loepard, I'll look into the ARFX stock and see what it has to offer...

Thanks guys on the ideas! Loving the info!

[melensdad]

Cav Arms is out of business but they sold their molds and the lowers are still be produced.

[Haraise]

Why do you want a lightweight 20"?

Going lightweight with that length of barrel is going to be front heavy, just a matter of leverage.

The velocity loss isn't bad at all going to 18, 16 or 14.5.

[ricsmall]

Ive heard some guys on another forum talk about plum crazy lowers, but it is a fixed A2 length stock.

[BigBluePup]

Why do you want a lightweight 20"?

Going lightweight with that length of barrel is going to be front heavy, just a matter of leverage.

The velocity loss isn't bad at all going to 18, 16 or 14.5.

I'm no expert but I plan on running it suppressed and from what I've been told the longer barrels are more forgiving when it comes to round development for sub sonic ammo.
That and I wanna keep all the steam I can to keep speeds up. even 100fps make a big difference when you start getting out to that 700yrd + range.

[BigBluePup]

Ya I'm not a big fan of fixed length stocks on AR's

[stokesrj]

The Bolt carrier is heavily milled but that's about it.

The reason I wouldn't go lighter is that I have several ultralight rifles, titanium actions from before they were available in factory form, carbon fiber barrels, skeletonized, everything, I just wouldn't do all that anymore, it isn't worth it. The weight of this one is just right. It performs beautifully, 300 yard shots on very small targets are a piece of cake, not even a challenge. And the handling and balance are superb. Going lighter can rob the handling.

The only negative is with the integral flash hider, the bottom is not solid. So, dust signatures, and dust in the eyes if shooting prone is a real possibility if you are not careful.

I could easily save more weight with my choice of scope and rings, but these are the ones I like. No irons for me, although I compete exclusively with irons, I want optics for hunting from touching fur to way out there, optics are faster.


But in the end, it isn't what I like that counts it's what you like. I was just sharing what information I have.

Bob