Shot Guns are often thought of as being the best firearms for home defense purposes. This does make sense as shot guns require less precision to be able to effectively hit an attacker. However, according to Richard A. Mann from Gun Digest (via guest post from the Daily Caller) the AR 15 is good candidate for being a prime home defense weapon.
Some of the reason are power:
Ballistically speaking, the AR-15 carbine chambered for the .223 Rem. is more powerful than the shotgun. With a nominal impact velocity of 1,250 feet per second (fps), a single 54-grain 00 buck pellet will have 187 ft.-lbs. of kinetic energy. This is very similar to a single bullet fired from a high velocity .22 LR. If you can hit your attacker with every pellet in a 00 buckshot blast, it would be like shooting the bad guy a bunch of times, all at the same time, with a .22. Home Defense: AR vs. Shotgun | The Daily Caller
Personally, at close range, which will most likely occur in a burglary/home invasion situation, having the most powerful weapon is not that necessary. A shotgun blast at five feet is quite deadly.
The author also notes that shot guns accuracy is limited to 25 yards.
The downside to all shot shells is range. Much past 25 yards, shot becomes terminally ineffective for two reasons. First, the pattern size expands to the point that a large portion of your shot will miss the target, and the resulting wound is less concentrated. Secondly, round shot is not very ballistically efficient and loses energy fast. If the engagement distance extends past 30 yards, it would be advisable to switch to a slug. Home Defense: AR vs. Shotgun | The Daily Caller
However, unless you are going to be shooting a fleeing criminals people outside your house, you’ll rarely fire at someone who is farther than 25 yards. The author recognizes the above criticism and concludes that . . .
The simple answer is to choose the one you can shoot the best. If you find the shotgun intimidating, it will never be a good choice. All the same, you might not be the person who has to wield it. The need to deploy the long gun in a defensive situation could fall on another member of the household. Home Defense: AR vs. Shotgun | The Daily Caller
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