first off, hello.  i'm Bobby and just bought my first AR.  a Bushy Carbine HBAR A3.  i love it.  already took it to the range to sight in and run some rounds through and it performed perfectly.  i never understood the AR fever until i got one.  now its time for the gizmos.  i'm going to put some sort of red dot on it, not sure which yet, but i don't want the front sight in the way so i ordered the DPMS four rail gas block and i'm going to put a flip down front sight on it.  the one i want is the GG&G one but they say it isn't compatible with the DPMS block but they didn't elaborate.  anyone have a guess as to why not?  and since the GG&G sight isn't compatible, what flip up front sight for gas blocks do you recommend?  thanks for any help all!  

Bobby

I use a DPMS four rail gas block on one of my rifles. I also use a YHM front and rear flip sight and it works great

cool! thanks!  it looks like its much lower profile when folded than the GG&G unit anyway which is what i'm looking for.  i put a TruGlo 2x red dot on it today.  i've read mixed reviews so we'll see how it works.  how hard was it to install your DPMS gas block?  any tip on getting it perfectly straight?  thanks again.

Bobby

Installing the gas block was pretty easy! You have to remove the flash supressor, remove the gas tube pin, the 2 pins on the FSB and gently slide the FSB off. I used masking tape to cover the FSB and barrel so if I missed (and I did miss) The punch wouldnt scratch the gun. Then slide on the new gas block, insert the gas tube and pin,  tighten the screws on the new gas block and reinstall the flash supressor. To adjust it I just eyeballed it then went to the range. I set the rear sight to mechanicle zero then I started sighting in.  It was a little off so I barley loosened the set screws and tapped it over then retightened it and it was only 2 clicks off on the rear sight when I was done. Maybe I got lucky but I've done it twice and had no trouble!!! once it was zeroed I loosened one screw and added loctite then tightened it and then did the other screw.