I'm thinking about picking up one of Bushmaster's 1/7 M4 barrels, but from what I've read these come with rifle feed ramps.  No problem, but I won't want to use an upper receiver with M4 feed ramps (LMT, CMT, etc), right?  It seems like that combination could cause feeding problems.

Who makes an upper without the M4 feed ramps?  I guess BM is one choice, but they seem awfully expensive (something like $170 for a flattop from BM).  Is there another non-M4 feed ramp upper out there that would be a good choice, but that's closer in line with the CMT or LMT's price?

And this is sort of out of left field, but would it make more sense to have someone dremel the M4 feed ramps into the barrel and then just get the CMT upper?

Quoted: CMT makes uppers with or without the M4 feed ramp cuts.

Well, crap, I didn't know that.  I guess that pretty much solves the problem.

Barrel with M4 feedramps with non-M4 upper= okay.

Non-M4 barrel with M4 upper = not okay.