Curious as to why you'd want an MTU contour barrel for a .223, particularly in that short a length. That's a pretty thick pipe for a shorty .223, especially if you feel the need to have it fluted to reduce the weight. There wouldn't be a great advantage in MTU contour for that purpose and you'd be much better off weight-wise with an M24 (or similar) contour for a .223. In any case, I have 30" MTU barrels in .308 that weigh a tick over 8.3 lbs. You can call Bartlein directly and they can give you a very good estimate of what your 16-18" MTU barrel would weigh, before and after fluting. Alternatively, Google "barrel weight calculator" and you'll find a variety of online calculators that can also give you some weights based on your dimensions.
