.223 barrel length vs .308 barrel length

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[ARCHIVED THREAD] - .223 barrel length vs .308 barrel length

Posted: 9/26/2005 7:03:24 PM EDT

Why is it that the .223 performs so poorly in the shorter barrel lengths yet the .308 doesn't seem to lose much of it's terminal ballistics in a 16" barrel? Is it because the .308 starts out so far ahead in ballistics to start with? I've been reading so much about how our military grunts are complaining about the M4s performance. Why not give them a rifle like the DPMS AP4 .308 for the CQBs? Why give them a unproven caliber like the 6.8mm to make up for the .223s short comings? Is this just a money maker for the defense contracters again? There is so much .308 history showing it to stop just about anything on two and sometimes four legs. Just look at what the sniper teams are still using for shots inside 900yrds.

Posted: 9/26/2005 7:18:25 PM EDT

[#1]

Beats me.

A 20" barrel on an AR only gets you another 50yds, or so, of frag range in comparison to the 16".

There was an AAR posted on here a couple months back saying that the typical rifleman kill was, on average, about 37yds in Iraq, and the average Sniper kill was about 75, or so.

Well within deadly for your average .223, IMO.

WIZZO

BTW, I love .308, though.

Posted: 9/26/2005 7:19:44 PM EDT

[#2]

Ever shoot a AR10/SR25/DPMS .308? Not exaclty a light, handy and soft shooting rifle.

Posted: 9/26/2005 7:36:04 PM EDT

[#3]

I dont understand. You are asking why the 5.56 performs poorly from 16" barrels? The answer is no it does not perform poorly.

Posted: 9/26/2005 7:45:13 PM EDT

[#4]

An instructor of mine once told me a story about hitting a VC 14 times with a 7.62 in order to put him down. Nothing that you can hold in two hands is going to assure you of a stop, so shoot him again. In the time that it takes someone to shoot a target twice with a 7.62, I will have run a failure drill and gone on to the next target with my M4.

Posted: 9/28/2005 5:56:53 PM EDT

[#5]

Why then the push for the 6.8mm?? If our guys are so happy with the M4s why are they reporting it taking 4 to 10 rounds to drop people? Ihave read alot on the .308s performance and have never heard of that round not delivering.

Posted: 9/28/2005 6:08:31 PM EDT

[#6]

Quoted:
Why then the push for the 6.8mm?? If our guys are so happy with the M4s why are they reporting it taking 4 to 10 rounds to drop people? Ihave read alot on the .308s performance and have never heard of that round not delivering.

With all due respect, what you have read is wrong.

The failures of the M4 can be traced to two things. One is M855 Ball, an inferior bullet in comparison to M193, and the other is failure to hit the enemy in the upper chest. One of these can be solved by traing, the other overcome through practice.

Posted: 9/28/2005 6:26:09 PM EDT

[#7]

I have no famous sources to quote, but 16" is about the minimum length for a 5.56mm barrel. At that length the bullet is going >2,700fps for at least the first 200 yards. The result is good disruption at the far end.

The issue with .308 is different. The bullet has more momentum because of its weight even at lower velocities. Standard velocity for .308 is less than 2,700fps anyway from test barrels. But I wouldn't own a .308 less than 18". At less than 18" the muzzle blast is fierce. A lot of unburned powder is just burning in front of the muzzle.

The bottom line is they are two different cartridges. A lot of factors go into what's the best barrel length. You have to look at what is going to work best for your particular purpose.

Posted: 9/28/2005 7:37:28 PM EDT

[#8]

Quoted:
Quoted:
Why then the push for the 6.8mm?? If our guys are so happy with the M4s why are they reporting it taking 4 to 10 rounds to drop people? Ihave read alot on the .308s performance and have never heard of that round not delivering.

With all due respect, what you have read is wrong.

The failures of the M4 can be traced to two things. One is M855 Ball, an inferior bullet in comparison to M193, and the other is failure to hit the enemy in the upper chest. One of these can be solved by traing, the other overcome through practice.

+1. It's about shot placement. At CQB ranges a .223 or .308 will put down a target with one shot if it's a CNS hit. Neither will if it's not a CNS hit.

Posted: 9/29/2005 12:09:29 PM EDT

[#9]

Quoted:
Why is it that the .223 performs so poorly in the shorter barrel lengths yet the .308 doesn't seem to lose much of it's terminal ballistics in a 16" barrel? Is it because the .308 starts out so far ahead in ballistics to start with? I've been reading so much about how our military grunts are complaining about the M4s performance. Why not give them a rifle like the DPMS AP4 .308 for the CQBs? Why give them a unproven caliber like the 6.8mm to make up for the .223s short comings? Is this just a money maker for the defense contracters again? There is so much .308 history showing it to stop just about anything on two and sometimes four legs. Just look at what the sniper teams are still using for shots inside 900yrds.

The 6.8 did not come from defense contractors either it came from end users who requested a larger round for the M4 platform. Also how do you recon its unproven? It had more ballistics studies in its design process than any round in history I am aware of. On the contrary its probably the MOST proven round. Also the military does not issue 16" 5.56 barrels. .308 DPMS for general issue? Too few rounds, too much recoil, too little reliability. You need to read LOTS before posting on this issue again. On second thought go to tacticalforums.com and post this question word for word in the terminal effects forum.

Posted: 10/7/2005 3:25:14 PM EDT

[#10]

Depends what you're use to shooting I guess. I find it no problem to control but I'm 6'3" at 220lbs so I guess it's relative to your physical size. I own a Colt Target Comp Match Hbar and a accucuracy systems mini-14 both of which totally rock!! However if the "you-know-what-hits- the-fan" I'm grabbing my .308

Posted: 10/7/2005 3:26:56 PM EDT

[#11]

What was he doing shooting him in the feet?????????

Posted: 10/7/2005 3:30:12 PM EDT

[#12]

REALLY!!!!!! This was from friend who just returned from over there in the 3rd Marine division and was a first hand account. I do agree completely with you on the ammo they're using!

Posted: 10/7/2005 3:33:20 PM EDT

[#13]

I you rely on ballistic studies rather than actual combat stats for round effects then hey it's your life!

Posted: 10/7/2005 4:00:01 PM EDT

[#14]

I rely on hat my instructors tell me about the men they have killed. They all agree on one thing. Shoot them in the upper chest until they fall down.

M193 or MK262 would solve most of the problems with the M4. 7.62N is just not everything that it is cracked up to be. Until the AR10 platform matures, there isn't a good weapons sytem to deliver it.

Nothing is perfect.

[ARCHIVED THREAD] - .223 barrel length vs .308 barrel length

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