Well, I said I was going to let it be, but I cannot. Mountain, if you're not hating on the M1A, you're decrying the 7.62 NATO/.308 in favor of the 5.56/.223.
If the 7.62 NATO did not have superior capabilities to the 5.56, why do police forces and the U.S. military (as well as militaries around the world) use it as a DM cartridge to reliably and accurately kill humans at distances of greater than 100-200 yards? If the 5.56 was so capable that it can easily do whatever the 7.62 NATO can, why would these organizations invest in more than one platform? The answer: the 5.56 is NOT as capable as the 7.62 NATO in fulfilling certain roles. Sure, a skilled shooter can make it perform excellently with a lot of time and practice. An equally skilled shooter could boost the 7.62 NATO's performance just as much. An AR15 could probably bring down a bear if you wanted to do so, but only if you have a combination of luck and excellent skill in shot placement. Sure, a 5.56 or a .22 can bring down a deer/human/whatever, but, again, it's all about shot placement. What if the many outside factors affecting your shot (how tired you are during WROL, how cold/hot you are, how uncomfortable you are, the adrenaline running through you, your heart rate, your breathing) prevent you from achieving that shot placement and you either miss or hit an area in which the 5.56 is not capable of seriously affecting?
If the 5.56 is just as effective as the 7.62 NATO, why have I talked to many Marines and soldiers who said they wished they could have had a FAL or an M1A chambered in 7.62 NATO issued to them instead of an M16/M4 variant, because of the enemy's ability to outdistance them or shoot through "cover" with an older, higher-caliber bolt-action rifle?
If you want to rely on the 5.56 and are comfy with it, then that's your choice and you should. You know your own mind, your own capabilities, and your own territory when it comes to defense. If you are comfortable with the thought that it will probably take 2-3 shots to knock an adrenaline-filled enemy effectively out of the fight, then go with the 5.56. No matter how you analyze it, any 5.56 load, when compared with a similar 7.62 NATO load, is not as powerful as a 7.62 NATO. If you want to be able to spray/suppress a lot more than 7.62 NATO users, then cool. Don't try to tell everybody else that because they take a different approach to defense that they are inferior. My M1A may have 10 fewer rounds per magazine, be heavier, and use more expensive ammunition, but the design is still battle-proven and reliable, uses a more powerful ammunition that is more likely to effectively take down a target in the first shot, is still able to make reliable kill shots at several hundred yards away if necessary, and can penetrate certain types of "cover" in an urban environment that the 5.56 cannot.
I prefer to have less ammo and a heavier rifle because I believe those two tools provide me with better abilities to survive: better chance to eliminate target with one shot, deny "cover" to the enemy, and make accurate kill shots at long ranges. If you like the faster-shooting, higher-cap AR system, I applaud you. You should fit your equipment to your mindset and your strategy. Just don't think that the M1A/7.62 NATO is inferior to the AR/5.56 in every essential way. It isn't. I've seen too many reports of failures of the 5.56 to stop hostiles in Afghanistan and Iraq, combined with the in-person reports I previously described, to possibly make me think that the 5.56 is just as capable of stopping a human (or anything else of similar size) as a 7.62 NATO. Shot placement, you say? Sure, if you can make the shot in that kill zone. Your target won't be standing still, you won't be calm, the environment won't always be nice for you, you won't always have time for precise aiming, and it is proven through battlefield reports that an adrenaline-filled enemy can not only withstand one round of 5.56, he can still return fire effectively despite it.
