So I'm planning a build out of one of the many m16a1 kits out there.  It will be built on a locally made A2 lower, so it won't be 100 percent a A1, but I have a question about the flash hiders.  I notice these kits come with a birdcage hider, which I'm guessing was later in the A1 timeline, but my question is when did the birdcage come around?  My dad is a Vietnam vet, drove a bulldozer and cleared jungle, and was issued a rifle that if he remembers had a birdcage on it, but in some of his pics I have seen rifles with the 3 prongs.  He was in country 69-70, and remembers his rifle was brand new when he got it, so, could this be correct?  He has also told me he may be wrong too, but figured I'd ask the hive.  BTW, our build is going to have a 3 prong hider

Some early A1s have them but for the most part it was phased out when the M16A1 was phased in.

The birdcage was one of the changes wanted by the military when upgrades were made to the XM16E1 and accepted as the M16A1 in 1967.

BUT...the more you learn about retro...the less set in stone you learn things were. Colt didn't throw parts away, and sometimes changes were made in country.

Thanks guys.  So since really my build isn't going to be a exact copy of a certain model I guess either one will work.  I'm going to go pull out dads photo album, and see if i can find a pic of a 3 prong...

Edit: cruised the albums real quick, only caught the muzzle of a rifle kinda out of focus (he was a engineer, they didn't use their rifles a whole lot, so not many in pictures of his)  Looks from what I can make out to be a birdcage hider.

Be sure and post pics as you build.  We LOVE tribute guns around here!

And on our behalf, please thank your dad for his service!

I sure will, as soon as I get the ball rolling.  Looking up the tools and such now

On this topic - how much of a mix-master can it be and still technically correct?  Perhaps not "as built" or "as issued", but "as repaired and re-issued"?  I suppose w/ an Air Force rifle anythings possible, and there are restamped M16A1/A2s running around.

While on active duty during the late 1970's (U.S.M.C.) the birdcage was the dominate flash suppressor for the M16A1. But there was plenty of rifles in service with the 3 prong. That I do remember vividly. What I don't have a clue about is were there any XM16E1 lowers still floating around with A1 trap door stocks? Wish I would of paid more attention at the time. Your father will be proud of you with his new build I guarantee ya!

Well, in my case, the lower I'm using is a A2, reason I'm using this lower is the company that it is made by is local, and their roll stamp uses their logo with the outline of WV.  Sort of showing some Wv pride along with building my dad a retro rifle.  the upper will be 99% of what is included int he parts kit.  so it's not like I'm going to go frankin retro

My lower.  This will be refinished in Norrel's along with the upper from a kit.

If you are building an A1, use the A1 birdcage-type FH. The 601 came with the duckbill 3-prong FH; the 602 came with the later 3-prong FH; the 603/XM16E1 (1963-67) came with the 3-prong FH earlier on, but was eventually changed to the A1 birdcage FH; the 603/M16A1 came with the birdcage FH (1967 - early 1980s).