Question, If I was to buy a DSA 20.0" F-Top upper and have the barrel cut back to a 16.0" upper or 15.“0 or 14.5” and install a DD M4A1 RIS II rail will the Gasblock hangout the end of the rail?
There are a couple issues here. First, the 20" barrel is going to be a rifle length gas system. While there are reportedly guys running 16" guns with rilfe length gas systems, the common shortest length barrel is 18". Second, if you decide you can pull it off, the gas block “should” end right at the end of the RIS which is 12.25" long. Why the Hell would you buy a 20" barrel and then hack it off?
I highly advise against chopping this barrel. If you do I wouldn’t go to anything less than 18".
Sorry, I was half asleep last night when I typed my question. DSA doesn’t make a midlenght upper in 1/7 twist. I guess I will have to wait for BCM to get the midlenght uppers back in stock. who eles makes a midlenght upper in 1/7 twist w/ M4 feedramps?
PSA makes (sells) a midlength upper.
Many times its easier to sell a barrel that is in a configuration you don’t like and replace it with one in a configuration that you do like.
“If you’re gonna be dumb you gotta be tough”