M16A2 or M4 Carbine? - Page 2 - Tilted Forum Project Discussion Community

sailor · 02-12-2006, 04:43 AM

Quote:

Originally Posted by Carn

The company Barrett is actually making an "improved" M4 that is going to be of a higher caliber. Supposedly it will behave like the 7.62 rounds, but smaller/lighter. It's supposed to be 115 or 120gr I think.

Interesting. I just found the following. Apparently its called the M468, fires a 6.8mm round, and is just an upper receiver, attaching to existing M16/M4 lower receivers to save on acquisition and maintenance costs.

http://www.military.com/soldiertech/..._M468,,00.html

Looks very interesting. I like that they moved away from the 5.56mm round--I personally think it's a underpowered, especially in the M4 which seems to be the weapon of choice in the types of engagements the Army has been involved in as of late...

ziadel · 02-12-2006, 03:21 PM

the 6.8 is not anywhere near being adopted by anyone. I dont even think any special units are even using it, and no private contractor would opt to use that weapon, ammo availability is just not there.

thats not to say that it isn't a great idea, it is, just dont expect to see anything come of it.

sailor · 02-13-2006, 12:54 AM

Quote:

Originally Posted by ziadel

the 6.8 is not anywhere near being adopted by anyone. I dont even think any special units are even using it, and no private contractor would opt to use that weapon, ammo availability is just not there.

thats not to say that it isn't a great idea, it is, just dont expect to see anything come of it.

I don't either. The US Army isn't about to retool it's operation for a new round. I think they should, like I said, I think the 5.56 is underpowered, but still, it's not going to happen anytime in the near future.

I like the M468 though. Seems like they put a lot of thought into it--using the existing lower receiver, same ballistics as the M4 to make training/retooling that much easier, etc--seems like a well thought out rifle.

But yeah, I doubt it's going anywhere.

ziadel · 02-13-2006, 08:27 PM

Quote:

Originally Posted by sailor

same ballistics as the M4

uh....no it's not. are you referring to the lateral transition it would be from the M4 to the M468?

I'm still not happy about it, we won't have a decent service weapon until we move away from direct gas systems, just toss a piston in the bitch and be done with it.

its really what is needed.
thankfully the FN SCAR is a piston gas system, as was the XM8, so direct gas has clearly been struck down from the running in any future weapons.

p.s. the 6.8 has lost some of its lackluster now that it has been conceded that the new gun really needs a new magazine system to work 100%, I think not having to buy another 50 million magazines would have been really appealing to the army, that shit adds up.

sailor · 02-14-2006, 01:23 AM

Quote:

In addition, while the SPC has a slightly lower muzzle velocity than the 5.56mm cartridge, its larger mass makes it ballistically similar to the lighter 5.56mm round (in terms of accuracy and bullet drop), and it delivers half again as much kinetic energy. In real terms, this means that the 6.8mm SPC has the same relative trajectory as the 5.56mm (which allows for the M468 to be fired and treated essentially like a 5.56mm M-16), but with 50% more stopping power, and a bullet speed of 2650 feet per second from a sixteen and one-half inch barrel, delivering 1715 foot-pounds of energy, with a six hundred meter effective range.

I'm not saying this weapon is what should be the next main battle rifle for the US Army. All I'm saying is that I find it interesting--I like that it uses a larger round, and I find it quite interesting how they've made it so that it would be much easier to adapt to than a new rifle system.

I really don't think we're going to see a new rifle for another 10 years though. Every development program has been scrapped, and no one seems too hot to trot to replace the M16/M4.

ziadel · 02-16-2006, 01:20 AM

Quote:

Originally Posted by sailor

I'm not saying this weapon is what should be the next main battle rifle for the US Army. All I'm saying is that I find it interesting--I like that it uses a larger round, and I find it quite interesting how they've made it so that it would be much easier to adapt to than a new rifle system.

I really don't think we're going to see a new rifle for another 10 years though. Every development program has been scrapped, and no one seems too hot to trot to replace the M16/M4.

okie, I get what your saying, the terminal ballistics are completely different tho and thats what we're after, better terminal ballistics.

and what is this 'we're not going to see a rifle for another ten years' stuff? We ain't gonna see anything like that because WE live in different countries

don't despair tho, the G36 is FAR superior to the M16.

sailor · 02-16-2006, 06:36 AM

Quote:

Originally Posted by ziadel

okie, I get what your saying, the terminal ballistics are completely different tho and thats what we're after, better terminal ballistics.

Ah, yes, OK, we were just talking about different things.

Yes, I too think we need better terminal ballistics than the 5.56mm round. It actually does create a very nasty wound profile in a person (certainly better than the 7.62mm round), but doesn't tend to stop them outright. A good example can be found here--one of the targets was shot 3 times in the chest from short range, and a fourth time taking off a testicle, and yet still fought--nay, wrestled--for several minutes before being subdued, and then survived to be carted off to the hospital to be patched up. There are several similar stories on that site, though I can't seem to find the other big one at the moment.

A great page on terminal ballistics is here. Check the 5.56mm wound profile at the bottom of the page. For a real nasty one, go look at the 30-06 round on the second page. Ouch.

debaser · 03-07-2006, 12:07 PM

Quote:

Originally Posted by Carno

The reason the M4 is less accurate is because of the barrel twist. It only has a 1:7 twist, which is not enough to stabilize the round before it leaves the barrel. The 1:7 twist is fine if you have a longer barrel, but the 14.5" barrel of the M4 is not enough.

A guy I know has an M4 that has a barrel twist of 1:9 and he says it is more accurate than the standard M16.

Of course that all depends on the type of ammo being used. Since standardization is king in the US military, the rounds they use are 62gr M855, which is fine for the M16, but less accurate for the M4 at range.

Some gucci spec ops guys are getting this kit, and I hear they all love that ACOG scope.

Ummmm...

A 1:7 twist is tighter than a 1:9 twist. The 1:9 was needed because the heavier 62gr M855 round will not stabilize in the 1:12 twist barrel of the M16A1. The spec-ops community is still pretty much limited to 5.56 and 7.62x51 if they want supply from the government (not third party suppliers, who are notoriously unreliable in Afghanistan). However many operators are now using a 77gr bullet out of a 1:7 twist that provides very satisfying terminal ballistics out past 200 meters even out of 11.5 and 14.5 inch barrels.

The M855 is just as accurate out of an M4 as it is out of an M16. The difference is in its terminal performance. A 5.56 round must fragment in order to sufficiently wound its target. To do that it must be traveling about 2500fps or faster. Out of the 14.5" barrel of the M4, an M855 will lose the neccessary speed after 50 meters, out of a 20" barrel that same bullet will travel about 150 meters before losing its "punch".

My problem with the ACOG is that if you are shooting from a dim or dark area into a brightly lit area the reticle will fade beyond the point where it is easily aquired for point shooting.

02-12-2006, 03:21 PM	#42 (permalink)
ziadel Myrmidon Location: In the twilight and mist.	the 6.8 is not anywhere near being adopted by anyone. I dont even think any special units are even using it, and no private contractor would opt to use that weapon, ammo availability is just not there. thats not to say that it isn't a great idea, it is, just dont expect to see anything come of it. __________________ Ron Paul '08 Vote for Freedom Go ahead and google Dr. Ron Paul. You'll like what you read.