M16A1 Duckbill Flash Hider

[Mosin Bubba]

Quick question for all you retro fans:

How common were the three-prong duckbill flash hiders on the original M16s? For most soldiers around that Vietnam era, would you be issued a rifle with an A1 flash hider or a duckbill flash hider?

I'm planning on knocking together an A1 build and was curious to know.

 

[243winxb]

I found good info here when looking up my M16A1 carbine, before i sold it. serial numbers, with photos.

Oops. No photos, thanks to Photobucket.

https://www.ar15.com/forums/ar-15/-/123-241681/?

 

[FL-NC]

I think the open types on guns without forward assist and shiny bolt carriers were more common on older rifles. Best way to know for sure is to search for images online of the VN war.

 

[Coop45]

Mine was new issue in mid '67 (three pronged with gold buffer) soon after that the ringed one started appearing with the new guys.

 

[MistWolf]

http://retroblackrifle.com

 

[AlexanderA]

Just to nitpick, the three-prong tapered flash hider found on pre-A1 M16's (and AR-15's) is not the same as the straight-sided "duckbill" flash hider found on certain prototypes as well as the Armalite AR-18/AR-180. Both these designs are open-ended but they look quite different. Properly speaking, "duckbill" refers to the straight-sided type.

The "duckbill" prongs had a tendency to bend, so the tapered prongs were a big improvement.

To answer the OP's question, an early A1 would have the close-ended "birdcage" flash hider, without the solid bottom. Therefore, it doesn't need to be indexed, and is installed with a split washer, the same as the prong type. The A2 birdcage has a solid bottom (to avoid kicking up dust, and to act as a compensator), so it has to be indexed. Originally, a peel washer was used for indexing. The crush washer came later.

If you are building an A1 rifle (with the forward assist), you should use a birdcage flash hider without a solid bottom, installed with a split washer.