Flat Top Upper Conversion

[Buccaneer]

AR newbie question here, I have a Bushmaster 16" A2 carbine and I want to convert the carry handle upper to a flat top. I was searching on AR-15, M16, M4, Upper Receiver and suspect that I want to get an assembled upper. However the uppers available show an option for an M4 flat top with M4 Feedramps in addition to a standard flat top upper for the AR15 and M16.

What is the difference and although my Bushmaster has collapsible stock and 16" barrel like an M4, will the "M4 Flat Top with M4 Feedramps" work? Sorry for the probably dumb question but I am a little confused. Thanks for your help.

[Smith]

Yes the "M4" will work. The feed ramps only make a difference in full automatic/3 rnd but is nice to have for what little difference they make.

[Buccaneer]

Thanks Smith, I appreciate your input.

[Smith]

Here is a pretty good article about "M4" feed ramps. M4 Feedramps - M4Carbine.net Forums & http://www.ar15barrels.com/gfx/feedramps.jpg