AR-15 front sight

[dlb435]

My front sight was pinned on a little off to one side. I've got to re-pin the thing. What size reamer do I need for the over size pins?

[ogree]

The size of the reamer would be determined by the size and kind of the pins you are using.
I had to do that once, welded up the original holes, aligned the front sight and then re-drilled them using the front sight base as a guide....what a pain in the a** that was cause I didn't have a fixture specifically made for performing that operation.
If possible....I would send it back to the manufacturer and have them correct it, that is less of a hassle.

[dlb435]

I've ordered a size 2/0 reamer and some oversize pins. Doesn't look like it will be much of a job. The original pins were 0.125 straight pins.

[LongRifles, Inc.]

Here's a trick used by the USMC PWS shop and by the better NRA service rifle builders.

Don't pin it. Drill and tap the holes in the front sight assy for set screws.

Set your rear site to MZ (mechanical zero) and then adjust the front base till it times up and shoots a no wind zero right down the pipe.

Good luck.