All,

Have been lurking here awhile looking for an answer to my problem.  Recently built up a rifle with a Stag lower and Armalite varmint 24" stainless barrel upper.  Everything fits nicely and seems to be fine.  Except.  When I went to clean the barrel prior to shooting, I discovered a burr at the gas port that won't let a Boresnake through.

Called the seller of the upper and he advised to push it out with a cleaning rod.  I did.  Haven't had a chance to shoot it yet.

Asked a local highpower shooter about this and he advised to shoot the burr out––definitely not to use a cleaning rod.

Well, I've already used the rod and burr is now pushed back up into the gas port.  Will I have a single shot AR as a result?  Will I do any harm by shooting it that way?  Can I easily remove the gas block and carefully remove the burr with a twist drill in a piin vise?

Any advise welcomed.  Thanks in advance.

Oilcan

+1
shoot the burr out

No harm in trying to shoot it out; worse thing that can happen is that you'll end up taking the front sight base off anyway.

It's not hard to remove the gas block.  I am assuming you have some kind of low profile and not a sight tower.  There are probably a couple of set screws on the bottom that you loosen so you can move it out of the way.  You don't have to remove the gas tube, but be very careful not to bend it.  There are stickies in the build it yourself section that should help.  If the burr is in the gas port it might make it's way back into the action and cause some mischief so you might want to remove it before firing.  Just my .02.