The H&K XM30 can be set different configurations, namely Assault Rifle, Carbine, Sniper, LMG, or Shotgun. However, the Assault Rifle and the Carbine configuration have the exact same stats, except that the Carbine uses SMG ranges instead of Assault Rifle ranges.
Since SMG ranges are dowright worse than Assault Rifle ranges, is there ever a reason to use the Carbine configuration? Or is there a bonus the carbine gets which I am overlooking here, like an idiot.
From real world differentiation between Rifles and Carbines, Carbines are more portable, use a smaller caliber (irrelevant since the stats are equal) and have shorter barrels. Could it have something to do with concealment?
Note: I did check the Run & Gun errata, but there was no entry regarding the XM30.