I am far, [i]far[/i] from an expert on this subject, but try to remain at least partially up-to-date on the current state of the 5.56x45mm discussion.  At any rate, I wonder if it has occurred to anybody if the alleged 'shortcomings' of the 5.56mm--which I've not yet heard corroborated by any of my friends in Iraq just yet, but won't simply dismiss out of hand, either--has as much to do with the [i]opponents[/i] that we're going up against as the cartridges that we're using against them.

A convinced, die-hard religious fanatic that is completely unafraid of dying, and is, in fact, [i]intent[/i] on dying in the process of killing Americans probably won't be stopped effectively to our satisfaction by [i]most[/i] calibers.  Add some readily-available narcotics into the mix (as was the case in Somalia) and you only make the situation even more dire.

There was an article in...[i]SWAT Magazine[/i]?  Or was it [i]Guns and Weapons for Law Enforcement[/i]?  Anywho, it related a story of a drugged-up perp that was shot at "point-blank" range with a twelve gauge shotgun something like six times and kept running.  Now, admittedly, the shotgun was loaded poorly (as I recall, traditional buckshot was not used), and only one of the shots was confirmed as even wounding him to any meaningful degree, but the point, I believe, is still at least partially valid.  If your opponent is sufficiently determined and/or drugged, the caliber of weapon used against him/her will almost always be inadequate from our point of view.

All that said, it is my opinion that the usefulness of the 62 grain M855 seems...dubious at best in the post-Cold War setting that we find ourselves in at this moment.  Sure, an armor-piercing round could have been justified when the armored Soviet horde was our primary measuring stick (and even then I would have found the concept of a general-issue AP cartridge to be something akin to fielding [i]only[/i] vegetarian MREs).  But on the modern battlefield, our most common opponents are almost certain to be [i]un[/i]armored irregulars.  As I recall, the Russians themselves were quite impressed (startled, more correctly) by the effectiveness of the older M193 55 grain round in Vietnam.  Where we were fighting unarmored irregulars.  Funny how that works, isn't it?

At any rate, I've been keeping my ear to the proverbial ground here and elsewhere on the status of the M16-series rifles, M4-series carbines, and the 5.56x45mm in general, and I think that simply fielding a new rendition of the 5.56 is all that is [i]really[/i] required at this point.  The 77 grain prototypes that I've been hearing about popping up out there in the Fleet sound like a good approach to a complicated problem, and with sufficient R&D, ought to do the trick.  The proposed 6.8x43mm round sounds interesting as well, but as others have pointed out, might or might not actually be all that necessary on a battlefield with perfectly good weapons chambered in both 5.56x45mm and 7.62x51mm.

Hopefully, the solution presents itself shortly, and hopefully, it doesn't wind up leading to an unnecessarily new weapon.  For my money, there's nothing [i]wrong[/i] with the M16 or the M4.  They're fine rifles; light, accurate, simple, and durable.  It's just the current cartridge that we're fielding that needs revamping to suit the weapons-system.

As [b]cmjohnson[/b] said, just develop a new and improved 5.56 for the weapons that we're fielding.

And that's something to think about.

blended metal bullets.

FWIW, I never said 7.62[b]x51mm[/b].  I'm just talking about the bullet.  :)

And to address Brett_Bass's ideas: we should investigate both solutions.  A better bullet in 5.56mm, and a newer round for special-purpose.  Since the invention of smokeless powder, we've been bracketing the ideal cartridge.  A while back, we looked at 6-7mm rounds to replace the .30-06.  The airforce bought the M16 to replace the M1 Carbine.

Whatever happened to using flechettes for close in work?

I always thought they looked particularly nasty coming out of a 90 recoiless.

today I bought two boxes of remington 55gr.223
SP ammo for fox/coyotes at my local walmart. I do think this round will kill a fanatic Iraqi has well has fox or a coyote. I really like the hydrashock hollow points as well. screw the convention.

Thanks for the reply, [b]blikbok[/b].  Good to know I'm not alone.

Interesting idea, so I thought I'd try it ;o)  Using my trusty QuickLoad program, I used the .223 Rem (SAAMI) with a 62 grain Speer and a 14.5" barrel.  Limiting myself to the 55,000 psi set as the max by SAAMI, I found that the 223 Rem would NOT give the desired 3200 fps by any means (I do not have the latest powders in my database, but the short barrel length makes it tough).

So I then increased the case volume, leaving the case length the same, which would be similar to chambering in the 22 version of the 6.8x43 and up.  I increased the case volume to as much as 3 times the original volume and found that the absolute max velocity I could get with the given parameters (62 gr, 14.5 bbl, 55K psi) was about 3050 fps.  Going to even larger case capacity DROPPED the velocity.  The optimum was about 90 grain water capacity, as compared to the 30.9 of the 223 Rem.

What this suggests to me is that if you want to achieve the higher MV from the shorter barrel, you will have to a) increase case capacity b) increase overall loaded length and c) increase maximum operating pressure.

The 223 WSSM does all this, but the number of rounds becomes severely limited.  Also, as velocity and pressure are driven up, barrel life will suffer, as many 22-250 AI or 220 Swift shooters will tell you.

The 6.8x43 may offer the desired performance, given the rather stringent parameters.  That is, if you want to use current lowers, uppers, magazines, etc with minimal modification.  Now, if we can totally redesign the whole kit, it becomes a new ball game.

Just some tryptophan inhibited thoughts

What actually IS happening with the 6.8mm?

I'd think that 6x45mm would be more doable.

The greater reliability of the FN MAG has been known for decades.  "Not invented here" was the only reason why we got the M60 in the first place.

My memory of the M60 is of using them in ROTC and IOBC and having the leaf spring fall off while firing, followed by the trigger group pin dropping out, leading to my having the gun in my left hand, and the trigger group in the other.  Not the worst machinegun we've ever used (Chauchat and M214/M219 win that award) but hardly the best either.  Also the only weapon I've ever fired that REQUIRED you to jerk the trigger.  I was instructed to do so in ROTC, and sure enough squeezing the trigger usually led to a malfunction.

I left active duty before I saw my first M240 or M249.

So far as the military, I don't believe much will happen. For the civilian market, who knows ?  Supposedly Barret is building an upper........

Want a caliber larger than 5.56 ?  Then move to 7.62. (IMHO)  That way you get an entire weapon designed for the round.

5sub

5sub

Yeah, I forgot about the leaf spring dropping out. Also the bipod wasn't very hardy. The dogs would break on the upper legs, causing it to no longer lock in place and hang limply from its mount. Still effective at putting down some good firepower on your FPL, though