AR 15 Bayonet?

[2ndAmendmentNut]

I have got an older Bushmaster Carbine with a 16" barrel and am wondering if a standard M16 bayonet will fit it? If not what size, style bayonet do I need? Anyone know where to get one?

[Combat Diver]

Standard bayonets are the M7, M9 and the newer Marine OKC-3S. The distance between the bayonet lug and muzzle device on the, 14.5"/carbine, 16"/middy & 20"/rifle, is the same, therefore they can all utilize the standard M7/M9 bayonet. Pics of my bayonets on 14.5" barrel.

M7 on M4
http://www.hunt101.com/data/500/Fix_Bayonet.JPG

M9 on M4ergy
http://www.hunt101.com/data/500/M4_build_with_M9.jpeg

Either will fit on the bayonet lug of your 16". The 16"/carbine differs in that the distance between the bayonet lug and muzzle device is longer than the above by approx 1.5"-1.75, therefore the bayonet sits too far back on the barrel, thus its ring is unsupported and the blade protrudes mere inches beyond the barrel (will wobble).
http://www.quarterbore.com/images/bayonet_pics/16inchwithbayo.jpg

There are a few bayonets which have been modified to work with the 16"/carbine, top is new OKC-3S, bottom barrel extended handle.

http://www.quarterbore.net/forums/photopost/data/529/medium/BayonetsOntarioOKC3S-ExtGenCutM7-MD.jpg

CD

[2ndAmendmentNut]

Thank you!