Due to the fact that the nearest outdoor rifle range was several hours away for nearly a year I was only able to shoot my AR15 with it's .22 LR conversion unit.   About 3 months ago I was finally able to shoot my rifle in the 5.56 Cal. load.  When I fired my weapon my rifle sailed to eject and cycle the next round.  I heard about how .22 LR's can gum and clog up the gas system so I decided I would check the gas tube first.  What I found was that the gas tube was completely blocked up with lead most likely coming from the gas hole in the barrel when I fired .22's.  

I cleared out the gas tube and made sure there were no other obstructions in it.  This past weekend I had a chance to test fire it again and received the same results.  Failure to eject.  I manually fed 30 rounds through my rifle in hopes of unclogging any blocked arteries but nothing worked.  The only thing I can think of is the fact that the gas inlet on the barrel must be clogged as well.  

Which leads me to my question, how do I clean the gas inlet on the barrel and do I have to remove the front sight tower to do so?  I tired to remove the front sight by drifting out the two pins but the darn things would not move.  Would I be better sending my rifle to a gunsmith to repair it?  Thanks for your advice.

Mac

You are on the right track!! It sounds like if your gas tube was that clogged, the the gas-port and/or the gas block/front sight is also blocked.

 One removing the front sight, remember the pins could be tapered. So looking down the barrel, from the rear toward the front sight, You drive the pins In from the Right Side and out fom the Left Side!!

 When yoiu do get the front sight off, don't forget to get That also!!

Good Luck,

Stuart

Quoted: there is a section of the FAQ dedicated to removing the FSB

Are the links in the FAQ ever going to be fixed? Would love to have access to them.

Thanks for the info.  I will take a look at the FAQ and see about pulling the FSB off.  

Have you try to soak the FSB section with Lead solvent for few days and shoot it without the gas tube installed to see if it will clear it?