Is it possible to change an AR-15 gas block?

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Jan 25, 2008
I recently bought a flat top A3 upper for my ar-15 and it shoots top notch. Problem is, i want to mount a scope or other optics on it and it came with the standard front gas block. (the huge thing that sticks up in the front and blocks a normal scopes view) Is there any way to change it so i came mount a scope with normal rings and not have to use the jerry rigged adapter for the hand rail?
Yeah. You just need a punch to remove the pin.

DISCLOSURE: I've never done this. It's only what I've been told. But upon examination, it seems accurate.

You can scope the rifle and leave the front sight there. You won't see it at any real magnification (I've heard it's undetectable as low as 3x). And if you go with an Aimpoint or EoTech, you can cowitness with the iron sights anyway.
Some are taper-pinned.
Some are clamped on with Allen-Head screws.

Changing the screw-clamp ones is as simple as changing it.

The taper-pin ones require a taper-pin reamer to ream the new gas block for the pins.

But, you will find the stock front sight is not even visible through the scope once you get past 3x or 4x power.

It is so close to the scope it is not in focus, and at most, and at low power, you may just see a ghost image of it, if you can see it at all.

Or you can just dremel the tower off.

Leave a little "meat" on your cuts, and you can dress the cuts to a nice contour with a file and sandpaper.

Degrease the area.

Tape the area so only the modified gas block is exposed.

Spray with Gunkote from a rattle can.

Let dry.

Gunkote on small parts can be "cured" with a hair dryer.
Moreover, just shooting the gun should cure Gunkote on a gas block, since it gets incredibly hot just from firing.

Its true too what they say about the front sight tower not being visible when a scope is used. I could not see the tower when I had this gun.

Thanks guys for all the replies! I had an aimpoint sight on it and of course the front site was plain as day. I just assumed a scope would be the same. I'll mount the scope and if i'm not happy i'll try and replace with a flat one. Thanks again guys!
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