Colt LE6920 upper on MT6400c lower?

[shrimpcaptain]

Will a Colt LE6920 upper fit on a MT6400c lower? Is front pin hole size the same?

[Frens]

it should.
a friend has a mt6400 with MTM40xxxx s/n and the pin is milspec size

[SpankMonkey]

Yes they are the same.

[shrimpcaptain]

Thank you both for the info. I'm planning to get another colt upper for my MT6400c. Here she is, I had ADCO install an A2 FH.

[warpigM-4]

I bought a MT6400 lower and put a 6921 upper on it sold it and got one of the new Colt M4 carbine Cal 5.56 Marked ones the MT had large FCG holes wasn't a fan of that but it worked fine