But it is simple fact and just plain logical, as well.
No, it is not a fact. One should not be forced to delve into the gory details to disprove such fiction, nor should such deception be disseminated into the minds of the American people with the clear motivation to terrify them into surrendering additional freedom or rights in exchange for a sense of blatantly false security.
Laymen tend to prop themselves up on widely speculated generalizations about a great many things indeed. To a laymen, concerning firearms, the large or longer the weapon the more powerful it must be. To a laymen, concerning bullet calibers, the longer the bullet the more deadly it must be. To a laymen, regarding AR platform rifles, they are chambered only in one caliber; the laymen does not know which caliber this is exactly or its capabilities, only that the military has used it for many years so it must be the most lethal caliber ever invented. To a laymen, handguns are useless for combat and only rifles can effectively kill scores of people on the battlefield. Lastly, to a laymen bullets in all AR caliber chamberings are the same shape, weight, and composition as those issued to and in use by our military forces.
When most laymen think of the weakest rifle caliber chambering in civilian hunting firearms they think of .22 long rifle, which is an exactly one inch long by 0.223" diameter, the same bullet diameter coincidentally as that dreaded bullet issued to our military forces. The .22 long rifle has been among the most common civilian hunting bullet since 1884. In the right hands the .22 long rifle can be deadlier than a .223 or 5.56mm (there are slight dimensional differences) military issue bullet. Countless hunters of all ages have harvested small game for the table using the .22 long rifle for over a century. If a skilled shooter decided to kill lots of people at once with a .22 long rifle capable of holding only five rounds—he could do it. Should the model of 1884 .22 long rifle hunting cartridge also be banned?
The 5.56x45mm NATO military issue chambering, also the most common AR platform caliber (.223 in civilian terms and with only slight dimensional differences) measures 2.26 inches in length and is just over two tenths of inch in diameter, and is not exclusively a rifle bullet. The 10mm auto chambering, most commonly considered a handgun cartridge, is 1.26 inches in length and .40" in diameter. The most common AR rifle barrel lengths are 16-20 inches. The most common 10mm
pistol barrel lengths are 4.5-6", which is up to 15.5" shorter than the longest common AR
rifle barrel length. And yet, when loaded with the most powerful +P loads available, the 10mm auto can not only approach velocities of the 5.56x45 NATO military issue bullet but also deliver more human tissue and bone damage, partially due to its much greater bullet diameter. Finally, there are much, much more powerful handgun cartridges commonly used for hunting dangerous big game that generate much, much more energy than the 13-1400 foot pounds delivered point blank by an AR-15 chambered in 5.56mm NATO. Thus proving handguns can be much deadlier than the AR in 5.56, and proving AR-15 rifles are not more powerful than handguns, as the idiotic OP professed to be fact.
Bullet composition/design is another concept most laymen do not comprehend. Military issue ammunition of specific and arguably more deadly varieties is not commonly available to the public, or is usually rare and expensive if purchasable. Nevertheless, most military issue ammunition is designed to over penetrate in order to get through thick clothing, wearable web gear and sometimes body armor and still retain enough energy to keep going. A 5.56mm issue full metal jacket military round will often punch through the human core or limbs and keep on trucking. That's not to say it won't do plenty of gruesome damage to the human body on the way. However, when compared to a fragmenting soft copper hollow point handgun caliber bullet designed to cause massive internal trauma to the human body, the 5.56mm rifle round can be considered the less destructive of the two.
Lastly, the 5.56x45mm military caliber can be chambered in a host of different
handguns much the same as common handgun calibers can be chambered in the AR rifle. So no, AR-15 rifles are not more powerful than handguns . . . that is simply not true and certainly not a fact. Claiming such to be fact is a scare tactic intended to instill fear in people who do not understand firearms or bullets or ballistics.