I would like to quantify my answer a little bit:
Ever since we had both longarms and pistols, we've been looking for an, 'in-between'. Through the years these have come in many forms. Early forms were short muskets and rifles. Later on they were relatively low-powered rifles with revolving cylinders.
Pre and post WWI pistols with rifle stocks were the answer (like the C96 Mauser and later the BHP). Right around and during WWII the submachinegun was concurrently developed in many different nations with several different designs.
During WWII, the first sub and assault rifles were developed. The US wanted a new PDW. It is notable that the M1 carbine was initially thought up as a pistol. However, the learning curve of a pistol was too was steep so a short rifle was developed. Of course, we all know about the German STG-44.
Post WWII we got into the idea that very small rounds at a very high cyclic rate would be just as effective at close range as a rifle with a slower cyclic rate due to cumulative damage. The most extreme example of this is the American-180 (.22lr at 1200RPM with drums ranging in capacity from 165 to 275 rounds each).
Right around the same time, more modern designs were developed (the Uzi dates from 1950 and the MP5 from the mid-60's). These stayed in favor until the late 1990's/early 2000's. Since then, M4's and CQBR's have come more into favor for several reasons:
-Better long range capability
-Better ballistics at short range
-Reduced risk of collateral damage
-Overall more flexible platform which is easier to adapt to dynamic situations
These are the reasons why federal, state, and local entry teams have switched from MP5's to shorty M16's. It is conspicuous that new rounds and projectiles have been developed to increase lethality and effectiveness at both short and long range even when utilizing a short barrel (such as the Mk318 Mod 0 SOST 5.56)
The PDW/carbine continues to evolve and will do so long into the future. One of the reasons I dislike PCC's in general and full size, non-FA PCC's in particular is the following:
-Pistol rounds use a fast burning powder. Any rifling beyond maximum powder burn hinders, not helps, ballistics.
-If you're going to shoot a target multiple times with a lower powered round (which is the intent) it makes sense to do so as fast as possible--this is where FA shines.
For example: When using something like an IMI Uzi with a 16" barrel and then SBR it to proper length (10.2") group sizes are reduced. This is because of the first point about fast powder and also because a shorter barrel of the same diameter is stiffer and therefore less prone to flexing.
[/long winded]
Yep. I don't see a point outside of FA. Even then (I own a registered FA Mac) it'll be the SBR AR first.
