A three-prong flash hider or an A1 birdcage flash hider, about the '66-67 time frame?  I'm building up an XM16E1 repro using a refurbed M16A1 upper, but my research shows both types .

Thanks!

The Variation Guide says the improved three prong flash suppressor was used from 1963 through part of 1967 on XM16E1's early M16A1's.  Soon after M16A1 production and just prior to chrome being added to the M16A1 chamber the birdcage was used.  So, I guess the answer to your question is either one would be appropriate, probably one not more appropriate than the other.  That is good, since now you get to pick the one that looks better to you.

Quoted: I'd use the 3-prong for the sexy factor.

I agree with you on sexy, Mike, especially since I'm using an NDS lower.  

Most of 1969 (II-Corps area with US Army) I carried a later-style 3-prong flash-hider ......... easy to snap-open the wire-band on a case of C-Rations in the field. About late-summer/early-fall we exchanged weapons for the upgraded "Bird-Caged Flash-Hider" M16A1.

You have to take those "charts" of when something was issued/modified with a "grain-of-salt"........some of the units didn't have their weapons "up-graded" until later than those dates.
I suspect that those chart "issue-dates" may have been a starting-point (?)....or possibly when "DEPOT" was suppose to have things done or an MWO completed (?)......but can only guess.

All I know is that we were an regular Infantry unit in the "bush"....and that rifle slept with me nightly.
Regards, RichardS in MI.