My first build had it's cherry broke today :-) It's a M-4 clone with the following parts ...
LCW lower and parts kit
LMT 16" 5.56mm 1/7 twist flattop carbine barrel with standard handguards and front sight
LMT enhanced bolt and carrier group
M-4 6-pos stock
Troy BUIS
Tacpoint dot sight
Brownells 20 and 30rd mags
Took it out today to run some UMC through it ... what lot of fun! Only a couple ftfs and double feeds with the 20 round mags. As I put more rounds through it, the smoother it ran. The Tacpoint had a couple for times where the light went out due to recoil, but after playing around with the batteries and spring, it stayed on.
My son had a hoot firing it too ... although he's been partial to my FAL in the past for fun shooting.
Next time I'm going to be a little more serious about sighting it in at a 100yrd range.