in the meantime I was able to fully disassemble a Walther-Colt M16: it's a f'in nightmare, beside being engineered as a toy, with the materials of a toy... if, as stated by usmcchet9296, it was stupid for Colt put on it their name, it was also stupid for Wather lowering their standard to make some money w. this thing : to perform the basic maintenance, a.k.a. cleaning the barrel , is mandatory disassemble all the (?)rifle, bolt included_ the same really thin barrel is brazed (!) to his chamber, and keeped in line with the rest of the rifle thank to the flash hider..._
I stop here, but the list is never ending_this thing is a yoke, as is a yoke the user's manual_ ABSOLUTELY DISGRACEFUL, regardless the selling price_