Quote Originally Posted by LDB View Post
Does anyone know of an upper with a rifle length gas system with a barrel shorter than 18 inches? Is that even possible?
LDB,

I can answer one of your questions with first hand knowledge..

Back in the day when I lived in the San Diego area Tim LaFrance took my 20" 1/12" twisted Colt pencil barrel and cut/re-crowned/re-threaded it to 16". It ran 100% up until i shot it out. That Colt semi auto rifle came with me several decades ago when I relocated to Idaho. The very 1st transferable Colt M-16 I bought ($2200.00) ended up with the upper in question. Naturally being new to machine guns I ran it really hard that first year. Being in a free state on a few acres of my own land, my home was my range.. you can imagine my enthusiasm.

Long story short it ran perfect up until it gave up the ghost and died. So yes, It can be done if you know what you're doing (Tim LaFrance). Give it to someone new to automatic fire on his own piece of land in a free state...you got a recipe for a burnt out barrel. I wish I still had it, great configuration...I'm talking about balance, handling characteristics & sight radius. This was before RDS and flat top uppers. It was a great set-up. That said...you'd be better off with a 16" mid-gas today.

Hope this helped answer your query.

openbolt