For most jobs the 5.56 SAW is going to have more than enough punch and offerAn M60E3 still weighs in at around 8.4kg and the M249 is about 6.75kg according to the literature I have available to me. You are right about the ammunition most certainly, the weapons with a full (standard) belt of ammo weigh 11.4kg for the M60E3 (100rds) and almost 10kg for the M249 (200rd DLB in a box). In short, close enough mass wise as far as the weapons empty/loaded are concerned. The basic role of any gun is to put bullets on the target and keep their heads down until you have/can remove(d) the threat. The question you should ask is, "What will do the job?" and not, "How big a gun can I get away with?".
a significant weight advantage over the lightest GPMGs. An M60E4 with
assault barrel is not much heavier than a standard M249, but the ammo is the
killer. 600 rounds of 7.62 is going to run about 18kg versus 9.5kg for
5.56mm.
As for the LMG/GPMG debate, it depends upon the role of the cell. If they need anything bigger than an LMG you are looking at a serious bit of firepower.
While the M-249 is an excellent weapon, there are rumors that the US Armed Forces would most likely had chosen something like the Chartered Industries Ultimax, had it existed at the time of the contract tender. This was due to its versatility (they have short barrels, silencers, the STANAG Magazines fit in the same well as the 100rd drum, and even a tactical kit!) A very big selling point for people who have to, "bring it all" with them. Another example is the CETME Ameli in the alloy option (5.4kg), broken down and in some sort of carrying case (obviously) for those times you need to be discreet!
As you can see, it all depends upon the role. If you need that .50 to hit a piece of light armour, then so be it! I would rather try to sugar the gas tank.... less dangerous than trying to lug a .50 over a hill and herniating yourself!!! =) Remember, we are still talking only four to six people, and not all of them are going to have the overall body strength of a heavy machine gunner. They still have to carry their own kit as well.
And of course, as mentioned by Mr. Matheson, how much ammo you can pull along comes into play. That great .50 or that GPMG will not be any good in its role if there are no more rounds for it... another reason for the switch to the lighter ammo. We aren't going into war in these scenarios, and if you are, be sure to get a bigger slice of the pie for having to carry 200rds for the Gimpy as well as a mortar bomb or two. Oh! Let's not forget the Milan(TRIGAT) round...... you see how quickly it gets ugly....
Speaking of carrying things....
I have been using a relatively simple formula for how much a person can carry before becoming too loaded down to move.
Carry Capacity:
(Con + Str + Wil)/300 x Character Wt.
Encumberance:
(Carry Capacity/Mass Carried) x Endurance & Speeds (value only considered if less >/= 1.0)
For example...
Agl: 45
Con: 54
Weight Carried: 55kg
Str:53
Wil:61
Wt.: 75kg
(54 + 53 + 61)/300 x 75kg = 42kg
42/55 = 0.76 x Endurance/Speeds
Endurance: 11 x 0.76 = 8.36hrs
Base Speed: 14 x 0.76 = 11 (Scientific rounding method)
Movement Speed: 15 x 0.76 = 11 (Scientific rounding method)
It's not unrealistic as far as the capacity of a person who is in relatively good shape and it has worked very well for my group (it also keeps them from lugging eight weapons, four thousand rounds and eight grenades).
It would also be fair to consider wearing clothes and armour to not counted against the overall weight, as they are worn and not that bulky... Should bulk come into the equation, then add the mass of the clothing to the total weight carried.
=|
S.