What kind of Drill for an AR sight install?

[JWH321]

I am installing an A2 style Front Sight/Gas Block to an AR-15 barrel using taper pins. The holes are to be 1/8 inch (#30). I will drill both the sight base and the barrel simultaneously.

Do I need an end mill bit to be sure that the barrel cuts properly or can it be done with a simple drill? Any recommendation as to the type of drill or end mill I'll need (I have a heavy duty drill press and a machinist's vise). I want to avoid having any possibility of the drill walking when it meets the rounded barrel.

I recognize that the holes will need to be taper reamed when I'm done, but I want the initial drilling to go smoothly.

Any and all advice will be appreciated. I've never done this before, but there's no time like the present to give it a shot.

 

[carbine85]

I would use an end mill bit and make sure the gas block is tight before you cut the grooves. Better yet get a good clamp on type and don't bother with the drill. Yankee Hill makes some good gas blocks.

 

[JWH321]

Thanks. I have a clamp on type, but I also have an extra barrel and I want to learn how to do the taper pin thing. I also am retired and messing with these things is cheaper than shooting ($.50 a round). It keeps me off the street.