Ultralight Ultralight Rifles

[StupidLightweight]

My preference is the forged slick side uppers. They're strong and lightweight. It's easy to mill the slot for the charging handle on whatever side you prefer.

Spike's Tactical AR-15 Slick Side Upper Receiver - Forged M4 Flat Top (Multi Cal)

Spike's Tactical AR-15 Slick Side Upper Receiver - Forged M4 Flat Top (Multi Cal)

www.joeboboutfitters.com

 

[KyleR1985]

My preference is the forged slick side uppers. They're strong and lightweight. It's easy to mill the slot for the charging handle on whatever side you prefer.

Spike's Tactical AR-15 Slick Side Upper Receiver - Forged M4 Flat Top (Multi Cal)

Spike's Tactical AR-15 Slick Side Upper Receiver - Forged M4 Flat Top (Multi Cal)

www.joeboboutfitters.com

Not my picture, but the CMT I posted is on the right. The one you linked - is it lighter than the CMT? I didn’t see a weight posted.

Seems like the cost of having someone mill it if you can’t puts it at the CMT cost.

 

[Welldone]

You dudes are some techno OCD freaks………MY kinda people

 

[packgoatguy]

This thread is my only "safe place" for letting out my gram counting obsession...

 

[Ferrulewax]

This thread is my only "safe place" for letting out my gram counting obsession...

You are in a safe space, with likeminded individuals. I spent an hour drilling holes in a saw last week to save 0.6ounces.

 

[goalie]

Grams are ounces, ounces are pounds and pounds are pain. I carried WAAAAAAY too much weight in the marines, I'm old and ain't got no time for heavy in my life anymore.

 

[BREAKCONTACT]

My preference is the forged slick side uppers. They're strong and lightweight. It's easy to mill the slot for the charging handle on whatever side you prefer.

Spike's Tactical AR-15 Slick Side Upper Receiver - Forged M4 Flat Top (Multi Cal)

Spike's Tactical AR-15 Slick Side Upper Receiver - Forged M4 Flat Top (Multi Cal)

www.joeboboutfitters.com

The spikes seems to occupy the sweet spot in weight vs preformance. The Fostech is magnesium, which really likes to corrode, especially when there's a chance for galvanic situations, like where the barrel, barrel nut and reciver all meet up. And the polymer ones that are lighter than the spikes, I'd question long term durability cutting a side charging slot in.

 

[khuber84]

Here’s my take. There’s two reasons to go 6x45 over .223. 1) legality in certain states. 2) increased performance from sub-16-inch barrels. That’s it.

No animal will know the difference. Put bullet in vitals, and lights go out in less than 20 seconds.

If not set up to load 6x45, would you suggest 6arc over the x45?

 

[StupidLightweight]

If not set up to load 6x45, would you suggest 6arc over the x45?

Depends what you plan to do with it, how far you shoot, and how strong you are for manually cycling a 6mm ARC. A .300 BLK, .350 Legend, or maybe even 6.8 SPC might work better.

 

[packgoatguy]

The spikes seems to occupy the sweet spot in weight vs preformance. The Fostech is magnesium, which really likes to corrode, especially when there's a chance for galvanic situations, like where the barrel, barrel nut and reciver all meet up. And the polymer ones that are lighter than the spikes, I'd question long term durability cutting a side charging slot in.

I don't know my metal properties... how does the magnesium/aluminum alloy aspect play into the corrosion problem vs straight magnesium?

If I'm seeing the weights correctly:

6.6oz Solo300
5.9oz spikes slick side
4.9oz fostech magnesium/aluminum alloy

 

[khuber84]

Depends what you plan to do with it, how far you shoot, and how strong you are for manually cycling a 6mm ARC. A .300 BLK, .350 Legend, or maybe even 6.8 SPC might work better.

I'm new to the manual ar game. As long as you have proper case sizing, and not running hot powder charges, extraction should be same as 556 or 6x45 no? Does the shorter case body result in greater stripping forces to load the next round into chamber? I'd like to have lower expansion velocity to 500y or so with 77tmk or 95tmk in 22arc or 6arc.

 

[StupidLightweight]

Yes, both should require similar extraction forces. I've only played with .300 BLK, 5.56, and 6mm ARC, but Thegman (our ULUL lord and savior who has much more experience) has a theory: the fatter the case, the harder it'll be to manually extract.

 

[JBradley500]

Not necessarily for weight, but I was getting paranoid that the bolt handle was too long so I gave it a quick shave and haircut.

 

[BREAKCONTACT]

I don't know my metal properties... how does the magnesium/aluminum alloy aspect play into the corrosion problem vs straight magnesium?

If I'm seeing the weights correctly:

6.6oz Solo300
5.9oz spikes slick side
4.9oz fostech magnesium/aluminum alloy

It's been awhile since I pulled any galvanic charts, but any time magnesium gets involved it like to corrode. Their exact alloy isn't disclosed, it's probably less of a deal than I'm making, but I personally avoid magnesium things after having to work with magnesium in a work setting.

 

[packgoatguy]

It's been awhile since I pulled any galvanic charts, but any time magnesium gets involved it like to corrode. Their exact alloy isn't disclosed, it's probably less of a deal than I'm making, but I personally avoid magnesium things after having to work with magnesium in a work setting.

It does make me curious though... several popular magnesium chassis on the market like xlr element and MDT hnt26. Wonder if there have been issues.

 

[C Bow]

May I ask what barrel nut you use

 

[Thegman]

Almost 4# exactly without the can.

View attachment 801714

Great job and very practical weight. I think that this is a good example that one doesn't have to pull out every stop to build a very lightweight, very practical rifle...all without breaking the bank.

 

[Thegman]

My preference is the forged slick side uppers. They're strong and lightweight. It's easy to mill the slot for the charging handle on whatever side you prefer.

Spike's Tactical AR-15 Slick Side Upper Receiver - Forged M4 Flat Top (Multi Cal)

Spike's Tactical AR-15 Slick Side Upper Receiver - Forged M4 Flat Top (Multi Cal)

www.joeboboutfitters.com

From what I've read anyway, ounce for ounce, forged is the strongest route, which probably means forged could also be the lightest (7075) option(?).

I'd be perfectly happy going full circle with something like this with a flat top. Maybe with the Palouse-lite features forged into the design as well.


I'd bet the Kaiser would just work fine as well, but not worth the $ IMO.



All that said, seems like with what we have available right now, the rifles can be pretty much as lightweight as we want. For myself, anyway, I doubt I'd want anything lighter than what I already have.

 

[Thegman]

View attachment 801810

Not necessarily for weight, but I was getting paranoid that the bolt handle was too long so I gave it a quick shave and haircut.

Does it work well being that short? Would probably help a little in keeping it from bumping your side when slung on your right shoulder.

 

[180ls1]

Fmk and new solo