This isnt a argument post. New guy in town is selling Core 15 AR'S they are piston instead of gas. I wasnt bragging on my Bushmaster he said ya brings yours up we will shoot I said sounds great he said but be prepared to spend some money after wards since youll get beat and want one of these......NOW Idk about you guys but this was the first of hearing about them. He then went to say the tolerances are tighter and better on these than yours and the barrel had a "tighter" twist.....mine is 1:9....his 1:9.... anyway I shot with him in three different styles....walking, prone, and bench.. walking I took without even blinking prone he took (ex-wanna be sniper who never made it) and bench I took shook his hand and said nice gun. Adter which he still was feeding me all this about how these are the new Colts and theyre better than the rest. MY QUESTION.....Whats the big hype about these things that he is telling me bc all i get from him is tolerances are better and tighter....he acts like its gold compared to copper.... and im not trying to offend anyone by saying what i said you jsut have to know the guy...