Follow disassembly instructions
The purpose of hand guards are to protect your hands in case you were to take a spill. Hand guards are also used to protect your hands from brush, such as trees, dirt, etc.., when riding in a heavy dense area.
In 1970, when I was in the military (US Army) I was learning to disassemble and assemble my weapon (M16) to clean it, and upon taking off the hand guards, I saw the word Mattel and their logo.............
Yellow tape
Try AR15.com Try AR15.com
If it is one of the recent Colt .22LR AR15 rifles, then the answer is no - they are completely different internally.
Yes, Jackie Robinson is credited with inventing shin guards and he wore hand made wooden ones.
1959
Yes
The US Army presently uses the M4 carbine, a shorter and much modified version of the Armalite AR15.
Colt has not offered a AR15 in 308
Yes, although, personally, I'd think it a waste to replace an upper just for one with a forward assist.
By it's serial number. Go to www.proofhouse.com and under 'long rifles' listing look for AR15 Sporter