Originally Posted by
saleen
Have you purchased the 14.5" barrel yet? If not, I would probably reconsider going with a 16" middy instead so as to avoid the issues of having a permenant muzzle device.
I have a 14.5 w/ a permenant flash hider to bring the length out. I put an ARMS #46 on it when I got it since that was the only way to add a free floated rail system at the time (2003-2004 I think). Once that muzzle device is on, it's on. I've seen people try and remove them, but it has ruined the threads to the point that they are unusable.
The DD barrel nut will in all probability fit over the flash hider, but it will not fit over any gas block that is installed, and it cannot make it over the barrel extension unless you pull the barrel extension off with a barrel extension wrench. I have never tried this before because I honestly don't think that I'd be able to get it EXACTLY right again. And even if the headspace was still acceptable, the front sight would likely be canted one way or the other I figure. You can avoid this by using a front sight / gas block that is of a two piece design like the YHM models, so there is a way around it if you must.
Earlier this year I had a friend of a friend send me a 14.5 SOCOM upper with a permenant FH attached and a standard front sight. He wanted a midlength LaRue rail installed, but there is simply no way to remove enough of the front sight to have a LaRue fit around it, so the barrel was unusable for the project and had to be replaced. That front sight ultimately had to be cut off so that a 2 piece YHM flip sight could be used with a standard length YHM rail system. Not overly sexy, but it was functional and served as a good present to Dad......
Another consideration you should make is that if you ever think that a sound suppressor may be in your future, it will make the replacement of the barrel a necessity.
If you just have to have the 14.5 / perm flash hider set-up, then have the flash hider permenantly installed only AFTER having the rest of the upper assembled.
Just my .02....
Saleen