The History channel is very much tuned for an entire population to watch and be entertained. Historians and aficionados can usually pick out the legit errors that are not arbitrary rather quickly. For instance, the AK47 family of rifles does not shoot the German 7.92x33, but rather the 7.62x39 Soviet cartridge. That is not arbitrary, that is fact. What is arbitrary is the [useful] range of the rifle.
I watched some idiot commentator on NBC, CBS, ABC, or CNN (I dont remember which) make a case for how deadly the AK47 is and that it should be outlawed in the US. The list facts he used was the AK's full auto rate of fire, the 1.5 mile range, the AK's pinpoint accuracy, and that it fires "cop killer bullets" because it can shoot through a bullet proof vest. Anyone who knows, truly knows firearms will laugh at all of those stats. First, not just anyone can own a full auto firearm, they are very expensive and special licensing is needed. %99.99999 of the AK's in the US are semi-auto only. Plus, the AK has horrible accuracy in FA mode. Secondly, the AK47 has a useful range of no more than 400 yards *in trained hands*. When fired at a 45° angle (not aimed) in to the air then sure, it might get out to 1.5 miles. Third, the AK is on the bottom of the pile in terms of military rifle accuracy. One of the things that make the rifle reliable is the very loose tolerances in its working parts, nothing is tight. A tight (for lack of better terms) firearm is a major factor in accuracy. Plus, the iron sights on an AK are flimsy and crude and they do not lend well for "pinpoint" aiming. Fourth, ballistic vests commonly in use by our peace officers are not bullet proof to any spire point bullet. Those vest are designed to stop round nose or lead bullets fire from handguns or low powered rifles.
Back on the History Channel's errors: I watched some show awhile ago comparing LMG's of WWII and they listed the BREN as having a 600 yard effective range but yet gave the BAR a 1200 yard range.

They ultimately had the same effective range, with the BREN having a slight edge in the general LMG role for a multitude of reasons.