ar fsb alignment

[bocefus78]

Installing a ff guard. How do I re align the fsb?
Tools in hand, please help.

Thanks!

 

[bocefus78]

Figured out there were channels for the pins on the bottom of bbl.
Shows my ar newbiness

 

[duffman0286]

I'm not so lucky on my Titan defense upper it's crooked... but something I've picked up building ak's and HK's is too use a string with a plumb bob...long as the barrel is straight up and down it works great

 

[Hookeye]

The barrel extension is torqued to 120 ft lbs IIRC. You can slip it just a bit to get FSB lined up.
Some folks bash the FSB with a rubber mallet (say it's in the field manual to do so).
Better IMHO to put a wooden dowel in the FSB and while sitting on the gun, just give it a nudge.
Some say you'll feel the pop. I never did.

My DPMS bbl was bought without front sight installed (FSB was there). Dunno if that meant it didn't go to a factory tweak process or not.
It's perfect now