Bullet Damage and Range for AR vs AK
The AK47 uses the Russian 7.62×39 round. It is basically a shorter .308, (with much less muzzle velocity) . These are “real world” effective up to about 200 meters, if you are a good shooter. At 100 meters from a bench, a decent shooter can get 4-6 MOA. Because of barrel thickness, round size, the actual bullet manufacturing, and the piston system (slightly off center), the AK is just not made for long or intermediate ranges.
Ammunition for the AK 47 is pretty straight forward. There are not a lot of options. 7.62×39 Ammo is relatively cheap for a rifle round. It ranges from $200-$350 per 1k rounds. FMJ and hollow point are both available.
The AK 47 SHINES at short range. (which it what it was designed for) It is an effective armor piercer and can shoot through cinderblock, 15 inches of wood and drywall very easily. The 7.62×39 round destroys whatever it finds within 70-100 meters. Due to its collapsible stock and destructive round, it is a force to be reckoned with.
The Ar15 uses the 5.56×45 round, or the civilian .223 Remington round. Many think they are the same, but they are slightly different. The 5.56 ammunition is slightly thicker cased especially around the neck of the bullet, it runs at much higher pressures than the .223 rem. A rifle that will shoot 5.56 will have no problem shooting the .233, but a rifle chambered in .223 cannot shoot the 5.56 without significant problems.
5.56 rounds do a few different types of damage.
—Fragmentation damage, when the bullet travels at speeds greater than 2600-2700 feet per second (fps) depending on outside conditions. (Under this speed, you can’t guarantee fragmentation.) The bullet will reliably shred and many small fragments will do quite a bit of damage. This usually happens at ranges within 200 meters, depending on barrel length etc. Mil. doctors have even reported that at closer ranges, the 5.56 fragmented…wound cavity is bigger than the 7.62×51 nato. The Viet Cong called the m193, “the inhumane bullet” because of its reliable fragmentation.
-”m193″, 55gr will reliably fragment out to 200 meters (20 inch barrel), 150 from 16” these actually peirce armor better than the m855 under about 60m
-”m855″. 62 gr will frag up to 90 meters, 140-150 from a 20”b. In fact, some of the trouble the military has been having in Afghan, is a result of using shorter barrels using m855 ammo. Many were using shorter barrels like 11.5 inch, 14 inch etc, and sacrificing necessary FPS to fragment.
-Wolf ammo has a thicker copper jacket and doesn’t fragment as the m193 does. Plus, wolf doesn’t travel at high/consistent velocities. Thus a much poorer round for defense. (not to mention the dirtiness, and steel case.)
—”Yaw damage,” meaning that the bullet will tumble, once it hits the person, will cause a greater wound cavity. Many think that a bullet will be more likely to tumble with different twist rates, but the twist rates really don’t affect yaw that much, as twist rates are more related to accuracy of heavier (longer) bullets.
—Expanding bullet damage. When using a hp, sp, ballistic tip, etc, (usually heavier bullets for longer ranges)…you are trading off the ability for the bullet to yaw, and fragment, and wanting the bullet to expand instead. As you get into higher grain bullets, your twist rate will need to be higher to retain accuracy, for example, 1:7, as opposed to 1:9. As a general rule, above 68 gr, you will want a higher twist rate than 1:9.
The AR15 can realistically hit a man-sized target from a rest at 300-350 meters. It’s maximum effective range can take it out to 500-600 yds. Some even claim 800-1000 yds with an 78-80+ grain bullet.(and still do massive damage) depending on the bullet weight, and design. The old myth that the bullet is anemic is just not true, unless you are using the wrong round out of the wrong barrel length, and twist rate.