Frist of all we need to clear up some facts first.
The 84mm Carl Gustav is a recoiless rifle. The round travels down a rifled barrel. It's not a rocket launcher like the RPG or Bazooka. It replaced the 90mm Recoiless in the Ranger Battalions, because it's a similar-type weapon, but much better perfromance. The thing weighs something like 30lbs empty though, so comparing it to the RPG's 20lb loaded is a bit of a stretch. Think of the Carl Gustav more as an anti-tank gun that's being carried by someone.
Now think of the RPG being 20lbs loaded with one round. That's alot of weight. Compare that to the LAW's 5lbs and you can see a huge weight difference. Yes, the RPG can be more effective, but you would have one guy, dedicated to that RPG. With the LAW a whole bunch of folks can carry one, which gives you that much more chance of not having the only gunner getting killed or not being in a position to take a shot. You also get volley fire, and pairs, neither of which you get with a single RPG. Yes, the RPG can be reloaded, but the LAW should be thought of the same as the RPG rockets themselves. One round of ammo. Only with the LAW, you don't need a launcher. So in the end, you can carry just as many LAW's as you could RPG rounds, only you can get them on target faster because you aren't trying to shove them through one launcher. Every round is it's own launcher.
Now the AT-4 is big and heavy. There could be a case made that really it's going to be too big and heavy for what we need, as our future likely opponents probably won't be tanks, and even when they are, the Army has alot of systems to deal with tanks. Going back to the LAW, or something at least smaller and lighter than the AT-4 might be worth looking at. I've fired real HEAT LAWs and they have plenty of blast on the other end for aything you might run into in an Iraqi city.
Now the USMC has the SMAW. It's based on an Israeli built system, that is in turn based on the RPG, that is in turn based on the Panzerfaust. Anyway, the SMAW is basically an RPG type weapon with western quality and performance. There's alot to be said for a sealed round, as it doesn't get banged up and damaged as easily. The RPG is known for a high dud rate, because the rounds are just open. They bought it with the express purpose of bunker busting, and it's a great system. The Army no longer used heavy weapons squads and platoons like they did in WWII and the USMC still does. Different doctrine, different weapons, different way of doing things. Maybe the Army needs a SMAW, maybe not. I'd like to see how the USMC is utilizing them in Iraq.
As for rifle grenades, they are no where near as effective as the 40mm. Rifle grenades and the 40mm pack about the same punch. Only the 40mm will go 400meters and the rifle grenade will go about 175meters. Also the 40mm is far more accurate than a rifle grenade as well. Add to that the fact that you have to take the rifle out of direct fire service (even if you're using a bullet trap RG) to shoot one, and it's easy to see the 40mm being a far more effective weapon than the rifle grenade.
As far as effectiveness of the RPG goes, just how effective is it? Sure it has a longer range and better penetration on paper, but how many vehicles get knocked out by them? A couple out of the thousands of RPGs fired. Even the Stryker seems to shrug them off with the cage armor. If they're only being used in an anti-personel role, then the more nummerous, lighter, and easier to employ LAW is a better system to use. They look bad ass and all, but just what are the facts on RPG effectiveness?
Ross