556 AR10 weight factors

[jpw062]

For bolt action rifles, it seems must are OK with an oversized action. Custom sporters are one example, but I think there are a large number of manufacturers chambering outside the prime size for their actions.
Same with shotguns. Manufactures produce 20 ga shotguns in 12 ga actions. Same with the smaller gauges. I have read some even use the same barrel blank with a smaller bore moving the balance of the weight forward along with greatly increasing weight.

So, why not a 556 AR-10? What is the weight differential? That is, equal set-ups, how much would an AR-10 in 556 weigh over an AR-15 in 556?

It seems there would be issues with the gas system, but an upper with a lighter bolt, adjustable gas system, etc, would likely be able to resolve this issue.

My hands-on experience with an AR-10 is limited to the most basic of familiarization with operating the platform. I am quite ignorant.

A pound?
Certainly less than two pounds, right?
It seems like much of the extra bulk would be in the upper and lower receivers which are aluminum, so not that much weight difference.

I know Colt attempted this a little over five years ago and it didn't seem to be commercially successful. I didn't find a clear weight comparison of their 223 AR10 and a like AR15.

Typing this out made me think of a "widdle receiver" that would convert an AR-15 upper to run on an AR-10 lower. What a complicated beast that would be. Reliably converting my mini to stanag mags would be considerably simpler.

 

[Varminterror]

You can’t pretend the same design rules apply to AR rifles as bolt guns, because they don’t.

It’s easy for a bolt action rifle builder to throw a short action bottom metal under a long action, but when you’re talking about AR’s, the magwell is integral to the lower receiver. 5.56 won’t feed from an AR-10 magazine, and would require proprietary magazines to do so. Feeding a short action cartridge in a long action isn’t always easy, and doing so in a semiauto is even more challenging.

So you’re engineering a new mag and lower to feed the rifle, which defeats the advantage of versatility with a common lower... all of that development cost sunk into something which is heavier and less reliable than an AR-15, and less powerful than a conventional cartridge AR-10.

 

[Insignificant bill]

Exactly

 

[<*(((><]

I’m confused as to the ‘why’ of your proposition? Is it to load longer?

 

[Casefull]

I’m confused as to the ‘why’ of your proposition? Is it to load longer?

Confused is the key to the Ops question. Maybe he stated it backwards, I wouldn’t know.

 

[Demi-human]

There is more than a plethora of ways to make an AR heavier...

https://www.brownells.com/rifle-par...ghts/ar-15-a2-buttstock-weight-prod10996.aspx

https://geissele.com/lead-weight.html

...without the added bulk.

Failing to mention all the other option for recoil reduction and muzzle control would be a disservice as well.

A good brake will soften the rifle more than a little. Lighter reciprocal components cause less loss of sight picture. A scope with a wider field of view can help it feel like it is not moving so much.

We actually want it shooting nicer, not just heavier, right?

 

[jpw062]

Question wasn't answered. I assume that is because no one knows. I thought it would be relatively simple for anyone who had built a few of each type rifle. I guess I was wrong.

The idea is not to make the rifle heavier. My guess is the difference is only about 1 lbs for similar builds. Not a problem for my uses.

when you’re talking about AR’s, the magwell is integral to the lower receiver. 5.56 won’t feed from an AR-10 magazine, and would require proprietary magazines to do so. Feeding a short action cartridge in a long action isn’t always easy, and doing so in a semiauto is even more challenging.

So you’re engineering a new mag and lower to feed the rifle, which defeats the advantage of versatility with a common lower... all of that development cost sunk into something which is heavier and less reliable than an AR-15, and less powerful than a conventional cartridge AR-10.

A magblock such as those used to convert ar15 to 9mm won't cut it?

The idea is to get one platform that shoots pretty much every round I want to be able to shoot.
Of all the crazy designs out there it just seems strange to me this isn't more common.
I thought I read the Colt was out of production, but it still shows on their website. Looks to me like it isn't an AR10 though.
https://www.colt.com/detail-page/colt-modular-carbine-select-fire
ANd there is a mag block, although it looks like a complicated design to me.
https://www.armsunlimited.com/Colt-LE901-Magazine-Adapter-Block-Conversion-Kit-p/sp99415.htm

I had not thought of the mag block before. That adds a level of complication and usually necessitates trial and error adjustments with each installation.
Maybe an AR designed to use mag blocks for all magazines similar to the new Ruger carbine... That seems to be a simple and reliable set-up. Also allow third parties to print specialty mag blocks.

I had a long action rifle that had been converted to shoot a shorter round once. The gunsmith just inserted a metal block in the back of the magazine so the cartridge was pushed to the front. Some adjustment of the follower of course. Worked well enough.​

 

[Varminterror]

It’s kinda like putting a 4 cylinder 1.8L engine into an F-250. It won’t do anything the 1.8L engine didn’t do before, except get worse gas mileage because the rolling gear and body weigh more. What’s really the point there?

As I explained in my first, there’s a necessary redesign to mags and or mag wells to accommodate the shorter 5.56 cartridge, and all of that expense just leaves you with an overweight rifle which doesn’t do anything more than an AR-15. AR-15’s are dirt cheap. AR-10’s are cheaper than they traditionally have been, but still aren’t anywhere near as cheap as 15’s. A mag block adapter and a specialty upper would likely cost as much as an entire AR-15, and still weigh too much when assembled, so again - what’s the point? AR-10’s are less popular than AR-15’s largely in part due to their increase in weight penalty - so making an overweight AR-15, under powered AR-10 hybrid just isn’t front of mind for many folks.

 

[Skylerbone]

For bolt action rifles, it seems must are OK with an oversized action. Custom sporters are one example, but I think there are a large number of manufacturers chambering outside the prime size for their actions

Let’s stop right there and say firmly that your assumption is based on the existence of oversized actions. If you delve into the archived threads you will find more than a few folks taking issue with this and specifically avoiding the one-size fits all approach.

Moving past that point, the AR-15 has enjoyed huge aftermarket support that goes well beyond furniture or triggers and into new calibers designed to fit its form factor that come awfully close to the performance range of the AR-10 with just a few parts swapped or even a simple barrel swap.

If you’re asking why companies aren’t beating a path to an AR-10 that rules them all, well, the economics don’t make sense. Now factor in the above penalties of weight, length, and reliability and ask yourself if such an animal could ever be described as “convenient”.

If you’re simply fixating on weight, Wikipedia will give you straightforward info on that, but again it’s only one factor. Why stretch your Cadillac into a Limo if you’re the one driving?

 

[Demi-human]

Question wasn't answered. I assume that is because no one knows.

You don’t know how to ask for what it is you want.

I thought it would be relatively simple

And yet the answers you received aren’t good enough...

One gun to work with all cartridges? And be good at none of them? With a bunch of extra parts to lose...

 

[Dibbs]

Have you looked into the new offerings in uppers for the AR-15, like 350 Legend, and 300 Blackout ? Maybe you are approaching this the wrong way.

It could be you can get calibers which do all you want, to shoot off a AR-15 lower.

BTW, it would save a lot of time, not to mention scorched gears, if you would state your purpose in the first post. Helps eliminate a lot of the
"what?" factor.

 

[Tommygunn]

........ If you’re asking why companies aren’t beating a path to an AR-10 that rules them all, well, the economics don’t make sense. Now factor in the above penalties of weight, length, and reliability and ask yourself if such an animal could ever be described as “convenient”.

If you’re simply fixating on weight, Wikipedia will give you straightforward info on that, but again it’s only one factor. Why stretch your Cadillac into a Limo if you’re the one driving?

Are AR-10s generally less reliable than AR-15s?

 

[someguy2800]

Nobody has bothered to make it because nobody in their right mind would spend twice as much money to build an AR10 in 223.

As far as size and weight goes a similarly equipped AR10 is about 2 lbs heavier, an inch longer, half inch taller. It’s not even remotely close to being able to put an AR15 upper on an AR10 lower. You have to have both in hand to really appreciate how much bigger an AR10 is. The size and handling isn’t even remotely similar.

 

[someguy2800]

Are AR-10s generally less reliable than AR-15s?

Generally people say AR10’s are more difficult to get to run reliably. An AR10 in 223 would be especially unreliable feeding because the feed ramps in the barrel extension would be in the wrong place for the cartridge size and there would be more unsupported distance from the mag to the chamber where the bullet could go nose up or sideways in the barrel extension because of the big bolt opening.

 

[Waterboy3313]

Moving past that point, the AR-15 has enjoyed huge aftermarket support that goes well beyond furniture or triggers and into new calibers designed to fit its form factor that come awfully close to the performance range of the AR-10 with just a few parts swapped or even a simple barrel swap.

That was thinking as well. If you want a heavier AR I bought a 24" inch heavy stainless .223 Wylde barrel. I don't even like carrying that from the truck to the bench.