While I've never had any time behind an A1, I've had a decent amount of time with the A2. Some changes are understandable, like the brass deflector so left handed people can use the rifle, and changing the forward assist button to a circle to save money and make it stronger. So why did the chnage the other things? I know the Marines are the only branch that actually use their elevation wheel to go out to 500m, but I could never ever see myself touching that think in combat. Secondly, why the heavier barrel? Only a small portion of it is heavier, but it sure adds a lot of weight. It seems like taking away AUTO and replacing it with BURST would be even more of a reason to stay with the pencil barrel. The buttstock was lengthened to a size that most people feel is too long, especially once you've got on layers of armor, clothing, etc. The pistol grip added that little hump between your middle and last two fingers, and all it does is give me a blister. Handguards a debatable, but I would think that the older ones would serve a better purpose as the bottom is flat, so you could rest them on a ledge or in the palm of your hand to get a more solid platform to fire from. A1 to A2 birdcage makes sense. Does anyone have any opinions on why things were changed the way they were? Today, it appears as if the whole XM8 program even started was to lighten the weight of the rifle. The original AR15 was something like 6 pounds with a full 20" barrel, right? Now the M-16A2 is approaching 8 pounds. That's a huge difference.