My friend got this in a trade.  Hoping this is the right place to ask.  It is marked on the A1 receiver with a "K".  Barrel is chrome lined and marked B MP 5.56 NATO 1/9 HBAR
Interestingly the short carbine length gas tube is used along with a front sight mounted where a carbine sight would be, but they added a second pinned ring for the swivel and forward ferrule to mount the rifle length handguards.  The handguards are very nicely machined to fit over the front sight.  Is this a bushmaster/quality parts upper?  I can't find any pictures where there is one with the carbine length front sight location, I only see the ones with the gas block under the handguards and the sight fully forward....

Any help appreciated

http://i1157.photobucket.com/albums/p587/burkefj/WP_00107728229_zpscab80a08.jpg

Frank

This really isn't the board. http://www.ar15.com/forums/f_3/118_AR_Discussions.html would be a better place to ask.

As for the the handguard setup that one is absolutely new to me.

Ok, I reposted there, we can kill this thread, thanks for the pointer....

I just got this back from Windham, the original bushmaster guys and yes it is a factory pre-dissipator!!

Hi Frank,

I just showed this to one of the old guys that was at Bushmaster even before me (I started in '98) and he said that is in fact a Bushmaster upper. What you have is the precursor to what became the "Dissappator" and they only made a couple hundred like that.


Erik Winter
Windham Weaponry
Gunsmithing/Tech Support
Office: 207-893-2223 ext. 756

Very cool.

I have an all factory Dissy from 1998.  I like those early HG's for some odd reason.