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[ARCHIVED THREAD] - 16" or 20"

Posted: 1/17/2006 7:15:31 AM EDT

Out to 300 yards will there be a difference in accuracy between the two? Thats as far as our range goes, so I wont need any shots past that distance. A few people have told me there wont be any difference between them, is that correct?

Posted: 1/17/2006 7:24:28 AM EDT

[#1]

Accuracy is determined not by the length of the barrel, but by its quality.

20 inches will gain you velocity.

Posted: 1/17/2006 7:43:52 AM EDT

[#2]

i'd go with the 20" it's not so long or short that it will cause a great deal of versatility issues... think of it this way - a 20" is often considered a standard barrel and the 16" is actually a stubby unit used for close quarters type work. with this premise in mind most people go with a 20" or 24" for shooting off bags - sometimes, but rarely a 16"...

check out some velocity tables online of 16" vs 20" vs 24" etc. the difference can be substantial depending on how you expect the bullet to perform...

as for accuracy... collin is onto the truth there - there are many technical things to consider, but for shooting with minor aid (optics, bipods, bags, etc.) at 300 you'd likely be better served with a barrel longer than 16"... - IMO, of course.

hope this helps.

septic tank

Posted: 1/17/2006 11:08:24 AM EDT

[#3]

Thanks guys. After reading your posts, and reading up on a Del-ton kit, I'm 99% sure thats they way I'm going. Even though my wife gave me the ok, I'm still going to keep it simple(or cheap as I can). Heres what I'll order:

20" Kit
M4 6 position stock- green
A2 flash hider or Phantom 5C2
Green handguard
Flat-top with t-marks
Everything else standard, I'll throw a green TangoDown grip on later

Seems doing it this way will actually save me about $100 in the long run.

Posted: 1/17/2006 11:38:23 AM EDT

[#4]

Quoted:
Out to 300 yards will there be a difference in accuracy between the two? Thats as far as our range goes, so I wont need any shots past that distance. A few people have told me there wont be any difference between them, is that correct?

Get both

Posted: 1/17/2006 11:42:02 AM EDT

[#5]

I will, one day. But for now I'm gonna go with the 20", seems to fit me better.

Posted: 1/18/2006 12:02:05 AM EDT

[#6]

Quoted:
Heres what I'll order:

20" Kit
M4 6 position stock- green

Just my experience for what it's worth:

20" barreled rifles with a collapsable stock balance funky.
Maybe a pencil barrel is OK, but an A2 will be muzzle heavy.
If you want a collapsable stock, get a 16" barrel and build a proper Carbine.
If you want a 20" barrel, get an A2 stock and build a rifle.
Just my two cents, take it for what you paid...

Don't fret over it though, in AR15.com fashion, you WILL end up with both eventually.

Posted: 1/18/2006 10:24:49 AM EDT

[#7]

Either way I'm going with a Del-Ton kit. So, lets say I went with a 16" barrel, besides being able to put a grenade launcher on it, does the M4 barrel have any other advantages?

Posted: 1/18/2006 10:31:51 AM EDT

[#8]

Quoted:
Either way I'm going with a Del-Ton kit. So, lets say I went with a 16" barrel, besides being able to put a grenade launcher on it, does the M4 barrel have any other advantages?

A "REAL" M4 barrel will be 14.5" long, have a chrome lined bore and chamber, a taller "F" height front sight base to accomodate a mil-spec carry handle or backup iron sight setup, it will have extended feedramps and a receiver with matching ramp cuts.

If you are just getting an M4 clone, then the only real difference is the step cut out in front for an M203.

Posted: 1/18/2006 10:35:09 AM EDT

[#9]

Cool, thanks alot.

Posted: 1/18/2006 10:42:07 AM EDT

[#10]

Quoted:
Either way I'm going with a Del-Ton kit. So, lets say I went with a 16" barrel, besides being able to put a grenade launcher on it, does the M4 barrel have any other advantages?

Think about how you're going to use your rifle the most, carrying around or just shooting on the bench.

I prefer the 16" for carrying around and plinking but I like the 20" better for target shooting.

I have both, actually two 16" carbines, a M4 CAR type and a mid length gas system (both with CAR stocks) and a A2 20" gov't profile rifle with an A2 fixed stock.

Bottom line is how you will use your rifle, I'm sure you'll get both later on.

Posted: 1/18/2006 10:59:12 AM EDT

[#11]

My wife hates this forum, she says everytime I get on here it costs us money

. I've got another week to figure out what I want before I place the order. 99% of the time this rifle will be used for going to the range and having some fun. I dont plan on entering any competitions, but I also dont think of this weapon as something for home defense(got a pistol grip Mossberg 500 for that). The range I go to only goes out to 300 yards. I'm kindof stuck, the advantages for either barrel really dont apply. The main reason I wanted a 20" barrel was because I thought it would have better accuracy past 150-200 yards, but that doesn't seem to be the case. I plan on putting a red-dot on it, so having the sights further down the barrel really does me no good.

Posted: 1/18/2006 11:06:39 AM EDT

[#12]

My thoughts on accuracy...

There is "intrinsic" accuracy and "practical" accuracy.
Intrinsic accuracy is checked on a benchrest with a high power scope.
Practical accuracy is checked in the field with iron sights.
Practical accuracy takes the sight radius into account, intrinsic accuracy does not as it relies on an optical sight.

So, with that in mind, the 20" barrel DOES have a longer sight radius and that CAN contribute to better field acuracy.
It really depends on what you are shooting at, how good you are and how good your eyes are weather you would be able to tell a lot of difference or a little difference between the two different setups.

Want the best of all worlds?
Get a mid-length 16" upper or better yet, a mid-length dissipator setup.
Mid-length sight radius is longer than carbine by 2", but the barrel is still short and handy.
The mid-length gas system also functions smoother because there is more barrel time before the gas gets tapped into the action.

Posted: 1/18/2006 12:33:38 PM EDT

[#13]

Quoted:
My thoughts on accuracy...

There is "intrinsic" accuracy and "practical" accuracy.
Intrinsic accuracy is checked on a benchrest with a high power scope.
Practical accuracy is checked in the field with iron sights.
Practical accuracy takes the sight radius into account, intrinsic accuracy does not as it relies on an optical sight.

So, with that in mind, the 20" barrel DOES have a longer sight radius and that CAN contribute to better field acuracy.
It really depends on what you are shooting at, how good you are and how good your eyes are weather you would be able to tell a lot of difference or a little difference between the two different setups.

Want the best of all worlds?
Get a mid-length 16" upper or better yet, a mid-length dissipator setup.
Mid-length sight radius is longer than carbine by 2", but the barrel is still short and handy.
The mid-length gas system also functions smoother because there is more barrel time before the gas gets tapped into the action.

Also, a longer, in this case 20 in barrel will shoot at higher velocities than a 16 in barrel with a similar bullet and load, and therefore the bullet will drop less at longer ranges (up to a point), but thats not really a difference in 'accuracy'

[ARCHIVED THREAD] - 16" or 20"

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