Do 20" AR-15's have a place?

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[ARCHIVED THREAD] - Do 20" AR-15's have a place?

Posted: 12/4/2013 3:45:09 PM EDT

Are there locations / situations where a 20" AR-15 in 5.56mm would be an ideal survival weapon?

It seems like for most urban areas, a lighter 16" carbine would be a better option, and if you get to the point where the extra fragmentation range of a 20" barrel would matter then you're probably better off with an AR10 (or AK or exotic caliber AR15).

Am I missing something?

Is there a sweet spot where 20" AR15's are practical, or are they just a legacy tool from the 1960's?

Posted: 12/4/2013 3:51:33 PM EDT

[#1]

probably more of an offensive weapon than defensive.

I like having mine, because I use it in NRA Highpower matches and CMP.

Posted: 12/4/2013 3:56:09 PM EDT

[#2]

I prefer a 20"...

I'm rural. I like a 20" for a few reasons. I still use iron sights, and the extended sight radius is somewhat more accurate for me. The primary reason I like the longer barrel I velocity.

I remain convinced that the 5.56mm's reputation as a poor stopper comes from a combination of two factors: The typical M855 62 grain bullet is less likely to fragment than the older 55 grainer. When coupled with the reduced velocities of a 14.5" or 16" barrel, the lower impact velocities and harder bullet mean the damned things are ineffective. I do stock soft point bullets, but cost considerations mean FMJ are cheaper. The typical 55 or 62 grain FMJ simply works better out of a 20" than a 16".

Longer sight radius. Higher initial and higher terminal velocities, leading to increased reliability with regards to fragmentation. Those are my reasons.

Fro

Posted: 12/4/2013 3:56:19 PM EDT

[#3]

I have M4s. My next buy is a 20". Because 'Merica.

Posted: 12/4/2013 3:58:47 PM EDT

[#4]

I intend to build an AR with a 20' barrel in 2014.

Posted: 12/4/2013 4:01:58 PM EDT

[#5]

I sure hope there is a place for them, since I have one.

Posted: 12/4/2013 4:04:10 PM EDT

[#6]

If you think there is, I have an upper for sale.

The 20" still is useful IMO. It's still being used in a DMR role by the military, and the USMC still finds it to be a good fighting rifle. My buddy really appreciated his M16A4 in a'stan.

I agree with what overscoped said, that it's better for offense than defense. In my uses, carrying more ammo with 5.56 is more beneficial than going with 308 for anything but a fixed position.

Posted: 12/4/2013 4:06:48 PM EDT

[#7]

Oh yeah! They have a place! I just built a flattop one last year with a nice scope, match trigger, and target hand grip. I'm gonna add a PRS stock shortly.

Look up a M10 sniper rifle, you'll get the idea, I think!

Posted: 12/4/2013 4:28:24 PM EDT

[#8]

Yes, the marines found this out the hard way in AFG

Posted: 12/4/2013 4:40:30 PM EDT

[#9]

My free-floated A2 upper is one of the few pieces I really regret selling over the years.

Posted: 12/4/2013 4:43:58 PM EDT

[#10]

That's what mine is

Posted: 12/4/2013 4:52:46 PM EDT

[#11]

For me personally, no.

I've come close to buying/building one a few times....same with a pistol AR. But for similar reasons they really have no niche they'll fill for me. For a short barrel, I'll take x39 every day of the week and twice on Sunday. For 16", 5.56 is just right in regard to range, recoil, penetration, etc. when you consider the overall package.

In a longer 20" barrel it just doesn't give me enough of an advantage over a 16" barrel. For distance (300yds+) I want .308 and bigger. That's why my distance guns are .308 to .50bmg. A .223/5.56 just doesn't compare well enough for my liking. I know others feel differently.

A 20" barrel also serves little purpose for home defense. My MSAR is great for hallways/stairs/doorways...hell it's shorter than a lot of SBR's and it's got a 16" barrel on it. Again, an extra 4" really won't matter in the home or around my property.

This is how I see it and what works for me.

-Emt1581

Posted: 12/4/2013 4:52:57 PM EDT

[#12]

My very first AR-15, back before the Clintoon-era ban, was a 20" basic gun. I still have it.

Posted: 12/4/2013 4:55:25 PM EDT

[#13]

My next build will be a 20". I live in a semi rural area, so it will work fine for me.

Posted: 12/4/2013 5:00:12 PM EDT

[#14]

If there was a numerical ratio for long and mid range efficiency, clip capacity, and availability of spare parts and ammunition, the 20" Colt AR15 would be #1 in America in every state.

This in my eyes makes it THE ideal survival rifle paired with a Ruger 10/22, Remington 870, and 1911 45. You could pick up a side arm in .38, 9mm, or .40 sw for ammunition variety.

A 14.5 barrel that is "lighter" for "urban environment gun fights" is a non sequitur to a realistic survivalist. If you are getting into urban gun fights you are doing survival wrong.

Just my 2¢.

Posted: 12/4/2013 5:12:24 PM EDT

[#15]

The notion of having a battery of firearms, each with their own purpose in a imagined scenario is not practical.

Pick one and learn to use it well.

Lugging multiple guns for SHTF scenarios is great in video games.
Reality is something else.

Posted: 12/4/2013 5:48:01 PM EDT

[#16]

This is Arfcom, Get all three! 24, 20, 16

My 24 hbar outshoots both my other ARs. It is not a good for close quarters cant be easily carried due to its weight (14 pounds) but is very stable when prone and has zero kick for super fast follow up shots.

Posted: 12/4/2013 5:56:10 PM EDT

[#17]

Light Perfection

Heavy Perfection (being fired by an Aussie)

Posted: 12/4/2013 6:01:14 PM EDT

[#18]

Quote History

Quoted:
I intend to build an AR with a 20' barrel in 2014.

View Quote

+1

Posted: 12/4/2013 6:18:36 PM EDT

[#19]

I guess i did it backwards. My most favorite and reliable AR has been my 20", owning a 16" here and there then finally settling with my 10.5"sbr.

I have both the 20" and the 10.5" now and nothing else. The only 16" rifle is the fiance's and she like it. I just have a hard time getting rid of my rifle, superb accuracy, not too heavy and ugly as sin but shes mine.

Posted: 12/4/2013 6:27:55 PM EDT

[#20]

Quote History

Quoted:
My very first AR-15, back before the Clintoon-era ban, was a 20" basic gun. I still have it.

View Quote

Me too, but I'm thinking about rebuilding it. Slapping a 14.5" LW barrel on the A2 upper, and moving the 20" barrel (which is a tackdriver) onto a DMR-type rifle.

Posted: 12/4/2013 6:59:00 PM EDT

[#21]

I think so. They added length is really not as bad as people act

Posted: 12/4/2013 7:26:06 PM EDT

[#22]

Quote History

Quoted:
The notion of having a battery of firearms, each with their own purpose in a imagined scenario is not practical.

Pick one and learn to use it well.

Lugging multiple guns for SHTF scenarios is great in video games.
Reality is something else.

View Quote

Who says you're lugging all three around? Or you're by yourself?

The idea of moving on foot solo with one gun as a nomad is pretty fanciful, and very harsh dangerous living. That kind of strategy is more akin to videogames than being well prepared with reliable guns in standard calibers thrown in the back of a diesel 4x4.

Just my 2¢.

Posted: 12/4/2013 8:09:33 PM EDT

[#23]

Heavy barrel for matches and the like . Very much a PITA to drag about but they shoot up a storm .
Or

Lots of folks who gripe and moan about the 20" rifles have never got their hands on a old school pencil barrel rifle.
Yeah they are a bit longer but they really have a nice balance and the irons work so much better . Lots of the good attributes go away pretty fast when you have a barrel any stouter than the pencil barrel though . Really needs a 20rd mag also .

Retro for retro sake is all well and good but any 20" lightweight has lots going for it . One of my most used ARs is a frankengun I built with a surplus 20"
barrel and a flat top upper . Very user friendly and versatile even if it makes a retro guy choke

Posted: 12/5/2013 2:51:49 AM EDT

[#24]

I have a HB Bushmaster 18" and keeps scoped shots in a 10" steel plate consistently at 800yd which
is as far as I can see in all directions...and some 16" for other purposes.

Posted: 12/5/2013 5:03:14 AM EDT

[#25]

I find a 20" with collapsible stock just as portable as a 16" for my rural environment.

Posted: 12/5/2013 5:05:17 AM EDT

[#26]

How much velocity does it add? So far there have been no real factual arguments, only sentimentality.
FWIW, this is why 6.8 fills a role for 200-300 yd shots.

Posted: 12/5/2013 5:32:55 AM EDT

[#27]

I stupidly sold my 20" a while back. I am planning on setting up a A4 upper with a nice optic in the next year after I get a Tavor.

Posted: 12/5/2013 6:22:16 AM EDT

[#28]

Quote History

Quoted:
If there was a numerical ratio for long and mid range efficiency, clip magazine capacity, and availability of spare parts and ammunition, the 20" Colt AR15 would be #1 in America in every state.

This in my eyes makes it THE ideal survival rifle paired with a Ruger 10/22, Remington 870, and 1911 45. You could pick up a side arm in .38, 9mm, or .40 sw for ammunition variety.

A 14.5 barrel that is "lighter" for "urban environment gun fights" is a non sequitur to a realistic survivalist. If you are getting into urban gun fights you are doing survival wrong.

Just my 2¢.

View Quote

Hate to point this out but it's a magazine not a clip.

Posted: 12/5/2013 6:24:27 AM EDT

[#29]

I have a predator pursuit which is a lightweight 20" rig and I really like it. I have it set up with a Nikon 4x16 monarch with mildots and that thing shoots really nice. Doesn't really help much at 100 yards where carbines are easy to shoot nice groups but when shooting 300 yards, my 20" beats my 16" hands down. If I had to pick one or the other... I like my lightweight carbine but the 20" is much better for hunting or other long range "stuff".

Posted: 12/5/2013 6:27:33 AM EDT

[#30]

Quote History

Quoted:
How much velocity does it add? So far there have been no real factual arguments, only sentimentality.
FWIW, this is why 6.8 fills a role for 200-300 yd shots.

View Quote

View this for a comparison

Posted: 12/5/2013 6:30:05 AM EDT

[#31]

Bayonets are also much cooler on a 20"

Posted: 12/5/2013 10:58:37 AM EDT

[#32]

Do 20" ARs have a place? Sure: the EE.

The velocity difference between 16" and 20" is very small (3-5%), so that there is basically next to no difference as far as trajectory. It you were worried about shooing at longer ranges, it might make sense to go with a 20" barrel if you were limited to ammunition that only fragmented above a fairly high threshold like 2700 (FMJ) or 2300 (BTHP) fps, but for most of use it would be more sensible to us a bullet that expands at much lower velocities (most of the barrier blind rounds expand at 1800 fps or lower). Federal Fusion bullets fired from my 16" AR will expand at well past 300 yards.

There are theoretical advantages to the longer gas system, but the data seems to indicate that the advantage is only theoretical. It is clear that when round are continuously fired until the barrel fails, an M4 barrel will outlast a 20" A2 barrel.

A 16" AR gives near identical performance, while being lighter and quite a bit more compact.

I like the look of an M16A4gery a lot, but don't have one anymore because I just don't see a need for it.

Posted: 12/5/2013 12:01:03 PM EDT

[#33]

Quote History

Quoted:

View this for a comparison

View Quote View All Quotes

View All Quotes

Quote History

Quoted:

Quoted:
How much velocity does it add? So far there have been no real factual arguments, only sentimentality.
FWIW, this is why 6.8 fills a role for 200-300 yd shots.

View this for a comparison

This is for M193 and M855 fragmentation, but for 62 grain bonded, 64 Grain GDHP or 77 Gr SMK I would trust a solid deer kill out to 220 yards and a person at 300-ish.
I only use 55 gr m193 for training purposes. It's not the best choice for fighting ammo, and we dont need to comply with Geneva Convention ammo guidelines.

Posted: 12/5/2013 12:06:36 PM EDT

[#34]

I love my 20" pencil barrel in A1 config. Lightweight, good balance, and accurate.

Posted: 12/5/2013 12:25:15 PM EDT

[#35]

The way the question is worded, the absolute answer should be "no"

Here's why:
Defensive shoots will be within 200m
While popping rounds at someone 800m away might sound tempting, it won't be effective in a SHTF environment. If all you want to do is say: "stay over there, don't come any closer" then the energy/velocity of a bullet at impact at 800m is irrelevant.

You need a weapon that works well indoors, in vehicles, and is convenient while slung when doing non-sexy SHTF tasks.

There is no place for a 20" 556 in SHTF.
They are awesome and I want one but NOT for SHTF.

Quoted:

Yes, the marines found this out the hard way in AFG

View Quote

Please explain how a company sized element employing 20" guns is the same as a homeowner in SHTF?
Then tell me that civilians are restricted in regards to ammo choices.

Quoted:
I intend to build an AR with a 20' barrel in 2014.

View Quote

Sweet, hopefully me too. Will it be your go to SHTF gun? WIll it have a place at all in your lineup?

Quoted:
I love my 20" pencil barrel in A1 config. Lightweight, good balance, and accurate.

View Quote

That wasn't the question

Quoted:
Bayonets are also much cooler on a 20"

View Quote

Not relevant in SHTF

Posted: 12/5/2013 12:31:17 PM EDT

[#36]

My first and so far only AR is a Colt Match Target with 20" barrel. I'm building 16" rifles for my wife and daughters though.

Posted: 12/5/2013 4:50:00 PM EDT

[#37]

My 20s are amoung my favorites.

Posted: 12/5/2013 5:32:45 PM EDT

[#38]

My only AR is a 20". I have a collapsible stock on it and love it.

Posted: 12/5/2013 5:56:40 PM EDT

[#39]

Quote History

Quoted:

This is for M193 and M855 fragmentation, but for 62 grain bonded, 64 Grain GDHP or 77 Gr SMK I would trust a solid deer kill out to 220 yards and a person at 300-ish.
I only use 55 gr m193 for training purposes. It's not the best choice for fighting ammo, and we dont need to comply with Geneva Convention ammo guidelines.

View Quote View All Quotes

View All Quotes

Quote History

Quoted:

Quoted:
How much velocity does it add? So far there have been no real factual arguments, only sentimentality.
FWIW, this is why 6.8 fills a role for 200-300 yd shots.

View this for a comparison

This is for M193 and M855 fragmentation, but for 62 grain bonded, 64 Grain GDHP or 77 Gr SMK I would trust a solid deer kill out to 220 yards and a person at 300-ish.
I only use 55 gr m193 for training purposes. It's not the best choice for fighting ammo, and we dont need to comply with Geneva Convention ammo guidelines.

I'm not disagreeing but it shows somewhat the difference in velocity between a 20 inch and a 16 inch barrel. I looked for a chart showing the actual velocity difference but couldn't find it with a quick search.

There is a substantial difference in velocity between the two barrels but I don't have an issue using a 16 inch barrel. A 16 inch barrel has plenty of velocity for most uses.

I have a couple of 20 inch rifles but if I was going to a gun fight...well I wouldn't go!....but if I had no choice, I'd bring one of my 16 inch barrel rifles.

Posted: 12/5/2013 9:54:53 PM EDT

[#40]

Will be building a C7A2ish in 2014 with addition of KAC M5 RAS as many soldiers bought them out of pocket for their rifles when overseas as opposed to the shitty triad rail.

Posted: 12/6/2013 2:02:44 AM EDT

[#41]

In my opinion? No, I would rather have a SBR, or a carbine. You will be doing far more carrying than shooting, and there is almost no possible way to justify shooting at the sort of distance where you would notice a benefit of a 20 inch. They're heavier, clumsier and longer for no tangible benefit.
Regardless, use what you like. It's a matter of preference, my experience shows little use for a longer rifle.

Posted: 12/6/2013 9:17:27 AM EDT

[#42]

The first AR I built was a 16". Couldn't find much use for it. I now have a 20". Can't find much use for it either, but at least I have kept it.

Isn't it funny...guys talk about how much lighter and handier the 16"-ers are, but typically they're loaded down with flashlights, bipods, forward grips, laser sights, etc.

20 years ago the .223 was considered an intermediate range varmint cartridge.. Nowadays, with the rampant infatuation of the AR platform, guys the cartridge was good enough for Cape Buffalo.

Posted: 12/6/2013 9:40:27 AM EDT

[#43]

I keep my 20" AR mostly out of sentiment: My Colt R6550k AR15-A2 Gov't Model was my first AR15, purchased in 1990.

That being said, it's every bit as lethal as my 14.5" and 16" carbines and I would have no problem using it in any realistic situation in which I would otherwise be armed with a carbine. It is also easier to shoot accurately with open sights.

Use what you want/like and don't worry about everyone else.

Posted: 12/6/2013 10:44:08 AM EDT

[#44]

Quote History

Quoted:
I'm not disagreeing but it shows somewhat the difference in velocity between a 20 inch and a 16 inch barrel. I looked for a chart showing the actual velocity difference but couldn't find it with a quick search.

View Quote

Found this for M855:

Also, check out this page: http://www.accuratereloading.com/223sb.html
This page is good too: http://www.ar15.com/content/page.html?id=213

There seems to be a 3-7% increase in velocity when going from 16" to 20".

Posted: 12/6/2013 11:04:30 AM EDT

[#45]

My first AR was a ban period Colt Match Target HBAR 20 inch. It was still the most accurate AR I've owned. I have 2 16s, but a 18-20 inch is on my short list.

I hate I sold it....

Posted: 12/6/2013 1:38:06 PM EDT

[#46]

Quote History

Quoted:

I'm not disagreeing but it shows somewhat the difference in velocity between a 20 inch and a 16 inch barrel. I looked for a chart showing the actual velocity difference but couldn't find it with a quick search.

There is a substantial difference in velocity between the two barrels but I don't have an issue using a 16 inch barrel. A 16 inch barrel has plenty of velocity for most uses.

I have a couple of 20 inch rifles but if I was going to a gun fight...well I wouldn't go!....but if I had no choice, I'd bring one of my 16 inch barrel rifles.

View Quote View All Quotes

View All Quotes

Quote History

Quoted:

Quoted:
How much velocity does it add? So far there have been no real factual arguments, only sentimentality.
FWIW, this is why 6.8 fills a role for 200-300 yd shots.

View this for a comparison

This is for M193 and M855 fragmentation, but for 62 grain bonded, 64 Grain GDHP or 77 Gr SMK I would trust a solid deer kill out to 220 yards and a person at 300-ish.
I only use 55 gr m193 for training purposes. It's not the best choice for fighting ammo, and we dont need to comply with Geneva Convention ammo guidelines.

I'm not disagreeing but it shows somewhat the difference in velocity between a 20 inch and a 16 inch barrel. I looked for a chart showing the actual velocity difference but couldn't find it with a quick search.

There is a substantial difference in velocity between the two barrels but I don't have an issue using a 16 inch barrel. A 16 inch barrel has plenty of velocity for most uses.

I have a couple of 20 inch rifles but if I was going to a gun fight...well I wouldn't go!....but if I had no choice, I'd bring one of my 16 inch barrel rifles.

Good answer!

Posted: 12/12/2013 11:16:04 AM EDT

[#47]

for all general purposes there is no real need for a 20 inch.

they are however the funnest to shoot IMO. Also for collector's value/ nostalgia they're WAY cooler

. I mean..every mall ninja has a carbine

.

[ARCHIVED THREAD] - Do 20" AR-15's have a place?

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