Before disuccing what the combat rifle should be, it's good to know the realities of combat. A start is reading "Operational requirements for an infantry hand weapon" by Norman Hitchman. To date, it is the only detail study of the effectiveness of rifle fire in actual combat, and was based on data collected from over a million casualties in WWII and Korea. Analysis of data procured in Vietnam, and the various Arab-Israeli conflicts also supported Hitchmans finding. Another good read is "an effectiveness study of the infantry rifle" by Donald Hall. You can get a great overview of these and other studies by reading Ezell's "The Great rifle controversy".
Basically, everything you know is wrong.
The average rifleman cannot engage targets beyound 500 meters. This is
primarily due to the fact that he cannot see the target because of
intervening terrain, camouflage, etc. Even if the soldier is capable of
shooting at longer ranges in formal marksmanship training. But it gets
even worse.
The majority of rifle fire is at 300 meters or less. 70% is at 100
meters or less, irrespective of terrain. This has been borne out in
Iraq, where most infantry rifle fire is in urban environments.
Firther, targets typically expose themselves for very short times. This
is the very reason the German army first adopted high cyclic rate MGs
and later the assault rifle.
The analysis in the Hitchman report ("Operational Requirements for an
Infantry Hand Weapon") contains some even more interesting material.
Contrary to legent, aimed fire has almost no effect on the production of
casualties. It is worth remenbering that Hitchman's data was from
actual combat, not armchair commandos.
"...rifle fire and its effects were deficient in some military
respects...in combat, hits from bullets are incurred by the body at
random:..the same as for fragment misileswhic..are not 'aimed.
..Exposure was the chief factor...aimed or directed fire does not
influence the manner in which hts are sustained...[Despite] evidence of
prodigious rifle fire ammunition expenditure per hit,..the comparison of
hits from bullets with those of fragments shows that the rifle bullet is
not actually better directed towards vulnerable parts of the body."
Since time and degree of exposure are the critical components in
producing a casualty, a lighter rifle capable of controllable
full-automatic fire was determined to be more effective thana
semi-automatic rifle. The M-14 is certainly not 'controlable under
fully automatic fire' by anyone's definition.
This is the reason that current research is focusing on weapons like the OICW/SABR/M-25. These weapons rely on 'smart' bursting munitions to increase hit probability.
Further, since infantry weapons only accopunt for a small percentage of casualties, most money goes to improved bomb, artillery, etc. Additional resources devoted to improve smallarms are likely to produce little or no additional benefits.
There are a couple of trends that are worth noting, however. Unban combat and counter-insurgency operations are increasing. This is likely to tilt requirements back in the direction of the individual soldier since big ticket items like smart bombs and tanks have little application in these operations. Unfortunately, expensive sexy projects like tanks and planes tend get more attention from procurement and development officers as these are better 'career' builders. No one care much about the infantry rifle (except infantryman).
The other nascent technology that may effect future combat is body armor. Current body armor is capable of defeating almost all existing small arms fire (excluding heavy machineguns, of course). Should body armor proliferate among our potential enemies, both the 5.56 abnd 7.62 class of small arms will become rapidly obsolete. A new generation of small arm will be required.
I expect the current generation of small arms to see only evolutionary improvement, with low cost improvements likely to be the only ones carried out. We are poised at a radical change in small arms and no one wants to finance an imporved 'longbow' when the next big thing is right around the corner. The Brown Bess served as the general issue rifle for over 100 years. It is quite possible the M16, with minor changes, will have the same kind of service record - and will eventually be replaces with a who new class of small arms.
