If your Ruger SR-556 didn't come with a sight adjusting tool (typically is found inside the box that has the gun lock in it) and you call Ruger to get one sent to you, give the person part #NS00084, SIGHT ADJUSTMENT TOOL, if they don't know what you are talking about.  One end fits the front sight, and the other end fits the rear sight.  Mine just arrived from Ruger (no charge).  It is long enough to fit in the front sight and works.  They will probably request your rifle serial number over the phone; they did on mine.  They may ask you to look inside the gun lock box if you haven't already done so.

Look in your plastic accessory pack I am told that is where it is located.

Do you have any carrier tilt?

Any of you guys tired of that question yet?

The factory front sight tool causes the carrier tilt.  Really.

HAHA!  Now that's the spirit!  Stiff upper lip and all that rot, old boy!

Yes to carrier tilt, but it appears to only be polishing the first 8th inch of the buffer tube between 5 and 7 o'clock as opposed to removing a lot of metal.  You can see it, but when you run a scribe across it, it just feels smoother than the rest of the inside of the buffer tube as if it is polishing off any machining marks.  I am making sure I put lubricant on the area and on the cooresponding area of the carrier.  On the face of the buffer itself are VERY light marks from the end of the bolt carrier.  360rds fired so far.

I am enjoying not having filthy upper and lower receivers after firing!

How?

Did you even read the OP?

Bad joke.