Monday, June 7, 2010

Dealie

Maybe my vast horde of loyal followers (all 3 of you) can help me out with an answer to this question. What is the deal with that 1 inch skinny section near the muzzle of AR barrels? The little dealie up there?

It’s beyond the gas system, so it isn’t part of that. It’s not like any other part of a bayonet lug that I ever saw or heard of. It didn’t show up on older M16s, so it is a relatively new development. It’s not ubiquitous, and I see it mostly on M4s and M4geries, but it is pretty common. Heck, maybe it’s ONLY on M4 types.

I just can’t fathom its purpose on my own.


Why?

7 comments:

Ben said...

Its a cut out for attaching a M203 to the barrel. Its more of a useless style thing for civilian AR15s. Mine has one.

Don said...

Correct. Check out this pic and you will see the connection point.
Usually this attachment point is hidden on a 20" M-16.

http://xbradtc.files.wordpress.com/2008/12/coltm4-m203-nsn-a.jpg

Anonymous said...

Even more fun! Quite a few "M4" barrels don't have the notch in the correct place, making it useless for mounting the M203.

Anonymous said...

Aye.

The... inelegance of this "feature" is one of several reasons I prefer a 16" middy configuration on my ARs, preferably lightweight (A1 contour) barrel.

Vinosaur said...

That is so your rifle can look "Tacticool". One of the things I HATE about my bushy, but I got it for a song and it has never had a single issus, so it is a keeper.

Geodkyt said...

As everyone else said, with the heavy barrel ofteh M4, the M203 wouldn't clamp on, so they reduced it where the clamps would go. Looks dumb on a non-military gun that will never mount a GL, just like mounting the bayonet lugged front sight housing on a 16" carbine with M4 length gas system (since the bayonet lug is 1.5" too far from the flash suppressor in that configuration).

Given the possibility for accuracy affecting issues from uneven stress relief in those cutout areas, I'd prefer to forgo the M203 cuts, even if I didn't think they lokked dumb.

But it's NOT present on a true M16A2 barrel, as they are skinny the whole length of the area under the handguards, and only heavy from teh FSH foreward.

Geodkyt said...

Good God, I wish this had a quick spell-check for my fat fingers. . .