Difference between an AR-10 and AR-15 in .308?

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davepl

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I was looking at an LMT308, which was beautiful, and then asked myself "What's the difference between an AR-10 and an AR-15 that's chambered in .308?"

I guess that's another way of asking other than caliber what's the difference, but to the uninitiated they look very similar. What are the significant differences, and is there an advantage/disadvantage to the AR10 platform over the AR15?

Thanks!
Dave
 
basic difference is the ar-10 is sized for the larger .308, thus it is quite a bit larger and heavier, but operation is pretty much the same.....Im under the impression that the AR-10 was the original (or something similar), correct me if im wrong.
 
The AR-10 is the AR in .308, but technically only Armalite's offering. I assume Armalite has a copyright on the name, as they made the original. Other companies call them by different names, but the design is the same.

An AR-15 is an AR in 5.56/.223. It started out as an Armalite, but Colt was brought in to add their production capabilities.

Interestingly, the AR platform was originally designed by Mr. Stoner to be a .308, but the military wanted the 5.56.
 
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"What's the difference between an AR-10 and an AR-15 that's chambered in .308?"

The difference is that there is no such thing as an "AR-15 chambered in .308."

It's a little like asking "what's the difference between an x-frame and a j-frame
chambered for .500 S&W?"

When scaling up the caliber, at some point you move off the AR-15 platform and on to the AR-10. 7.62x51 (.308 win) is past that point (7.62x39 is not, however)

There are many parts commonalities, but many differences as well. Most of the common parts are furniture like stocks, grips, handguards, sights & optics. Most of the differences are, aside from the upper and lower receiver, internal. I am not sure about the controls like the selector, bolt release, and mag release.

Edit to add: As said above, "AR-10" is specifically an Armalite rifle and "AR-15" is a generic term, but Most people understand when you say "AR-10" you are talking about a generic AR-10 pattern rifle.

Second edit: Onmilo is correct. I must have Mosins on the brain.
 
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As mentioned above...

7.62x51/.308 Win cartridges won't fit in a regular AR15 magwell.
And the carrier doesn't have enough travel either.

AR10/LR308 have longer receiver, carrier, magwell and magazine
to accommodate the longer cartridge.

The regular AR10/LR308 cannot handle .30-06 or longer cartridges.
Some manufacturer made a longer version in .30-06 once,
but I don't remember which one.



There are some really smart AR 'wonks' on this Forum,
they'll be along shortly to tell you more details regarding history and origin.
 
To extend the revolver analogy used above, an AR-15 is a "small frame AR" and an AR-10 is a "large frame AR", if you want to look at it that way.

Among other things, the AR-10 has a longer magwell than the AR-15 and will accept longer cartridges, like .308. That round is too long to fit through the AR-15's magwell.
 
My Armalite AR10 also dresses up well with her 338 Federal upper when she is out slumming. My next shopping spree i may get her a 300 upper.
You can't dress up your AR15's that way.:neener:
 
AR-10 is a specific rifle made by ArmaLite. LR-308 is a specific rifle made by DPMS. One really should use the correct terminology as the rifles are different and many parts do not interchange. The 7.62 AR platform can use a cartridge up to a .308 length and is available in several different calibers, as is the AR15 is available in different calibers.

This FAQ well tell about the different manufacturers.
http://www.ar15.com/forums/t_3_62/378850_AR10_FAQ_and_information_Small_Update_Sep_2011.html
 
Technically, the only AR15 is made by Colt. All others are just AR platforms but no others can legally call themselves AR15 as no other rifle besides those from Armalite can call themselves AR10s.
 
...advantage/disadvantage to the AR10 platform over the AR15?
Cost of equipment and ammo favors the latter. More power downrange the former, plus larger & heavier than the 5.56.

The original ArmaLite design by Stoner was in the 7.62x51 NATO round. No one wanted it (besides the Portuguese?)

http://en.wikipedia.org/wiki/AR-10

So they designed a smaller version, sold rights to Colt, which became the AR15/M-16.

I've heard it said that Colt is coming out with a .308 version... but who knows? Talk is cheap.
 
Miitary sales of the large mag AR-10 are pretty much limited to 5,000 unit contracts to field a one time only requirement for a tactical long range precision rifle. The Brits use one, and the Germans recently were noted doing that, too.

The AR15 can be had in over three dozen different cartridges, but they all have an overall mag length restriction of about 2.300 inches. They are predominantly "intermediate" cartridges, most designed in the last forty years, unlike the larger military rounds. Those haven't been tinkered with much at all since the introduction of intermediates. The .308 was about the last of it's breed, and it was a logistical and industrial compromise from day one. Like V8 gas motors, some just can't let go of the .30 cal despite it's obvious drawbacks. They have a place, at 3.25 a gallon at the pump and rising, they aren't the most efficient means to an end.

It's confusing when so many of the listed cartridges for the AR15 start with .300 or 7.62, but it's a matter of just being aware the size of the bullet does NOT automatically mean it's being propelled faster or hits harder than a smaller one. That's determined by the amount of powder behind it, and that's where the newer shooter discovers there's a lot more to learn about guns.
 
I've heard it said that Colt is coming out with a .308 version... but who knows? Talk is cheap.

It's been listed on their website for quite some time now, however i believe it has yet to reach the civilain market. The CM901, or SP901 is a .308 AR pattern rifle that also has the ability to accept any mil-spec AR-15 upper.
 
Most of the common parts are furniture like stocks,

Need to be careful with stocks as some with a cheek riser or swell will interfere with the full motion of the charging handle.
 
Like V8 gas motors, some just can't let go of the .30 cal despite it's obvious drawbacks. They have a place, at 3.25 a gallon at the pump and rising, they aren't the most efficient means to an end.

I feel it is neceassary to point out that there are more V8-powered vehicles in production currently than over the last 30 years, and many of them get well over 20 MPG in full-size cars (Cadillac, Charger, etc) and even trucks. They tend to be more efficient in heavier vehicles than smaller engines.

While I see what you're saying, I don't think it's a good analogy.
 
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