The URGi program specified commercial off the shelf parts. It uses a standard Daniel Defense 14.5” mid-length barrel. Which are excellent, one of the very best barrels you can buy.
There’s mid-lengths, and there’s mid-lengths. I’ve seen 16” mids ported from .071”-.082”. Once the port is past about .073-074” whatever benefit you thought a mid-length had is long gone.
I would prefer a proper 5.56 chamber and .0625” gas port on a carbine over how most mids are built these days.
Nothing so needs reforming as other people's habits - Mark Twain
Tact is the knack of making a point without making an enemy / Where is the wisdom we have lost in knowledge?
The bottom pad is actually more prominent. The outward facing surface is all flush with the upper serrated paddle, and the whole thing is serrated. So there's a little more beef in the part for strength and it's easier to use to manually lock the bolt back than a standard catch. But it's not a big, snaggy paddle like the Geissele Maritime bolt catch. I like it as a mild but unobtrusive upgrade.
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Not another dime.
I paid $499.00 for a CCU upper on 5/13/19. On 12/27/17, I bought a complete M4 lower from them for $199.99 after a $20.00 discount. Thus making my only complete Colt - if you excuse the ToolCraft BCG, and the B5 Bravo stock. All told less than $850.00 in the base rifle.
Adding nothing to the conversation since 2015....