I think I need a refresher here...

I know that bayonets fit properly on rifles with a rifle gas system and rifle barrel, on carbines with a Car-15/M4 gas system and 14.5" long barrel, and on midlength guns with a middy barrel and gas system.  I assume that a 14.5" barrel with a pinned extended FH would also accept a bayonet AOK, and the FH would simply protrude a bit more than normal.

I know that a bayonet will hang behind the flash hider on a 16" barrel, but how do they look on 14.7" barrels with a pinned A2 FH?

I'm getting started on a retro-ish carbine, but I don't know exactly what route I want to go yet.

Thanks guys!

My CMMG 14.7 looks and works fine with a bayonet.

Found this on Google for ya, hope it shows up.
Guess well find out.http://www.google.com/imgres?imgurl=http://www.ar15barrels.com/tech/bayonet-lug-position.jpg&imgrefurl=http://www.ar15barrels.com/tech/&usg=__T3fYU9-Rn093saKEBt8X3rvzEIo=&h=726&w=700&sz=85&hl=en&start=85&zoom=1&tbnid=LM323-CYVwpsgM:&tbnh=140&tbnw=132&prev=/images%3Fq%3DM4%2Bwith%2BBayonet%26um%3D1%26hl%3Den%26sa%3DN%26rls%3Dcom.microsoft:en-us:IE-SearchBox%26rlz%3D1I7TSNA_enUS361US364%26biw%3D1184%26bih%3D591%26tbs%3Disch:10%2C2128&um=1&itbs=1&iact=hc&vpx=124&vpy=251&dur=12106&hovh=229&hovw=220&tx=107&ty=192&ei=PJSMTK3CIoqjnQe72pWoDA&oei=_ZOMTLyyH6LknQeaz6S0CQ&esq=6&page=6&ndsp=17&ved=1t:429,r:0,s:85&biw=1184&bih=591

See:  http://www.quarterbore.net/forums/showthread.php?t=43