Question About Zeroing an Ar-15 with iron sights

[d.kaufman]

Not sure you can do that. Pretty sure when threads get stripped, there isnt any material left to re-thread, unless you step up to a bigger hole, but then it wont be compatible with any sights.

Pretty sure if its stripped, its done for in this case.

Heli-coil

 

[Cameramonkey]

Heli-coil

Interesting. I wonder if they make them in the weird 36tpi size?

 

[d.kaufman]

Interesting. I wonder if they make them in the weird 36tpi size?

Never looked into it but a place like Fastenal is where I'd look if it were an abnormal thread

 

[shootersix]

Is there any sign that the front sight has been changed?

I know that there are 2 different size railed gas blocks, one is rail height, and the other is low profile once I had a guy bring in his ar and had the same problem as you, his problem was he had a rail height block, and a front sight for a block height, so he maxed out his adjustment and was still shooting low.

Now if you have the fixed front “triangle” sight, this won’t be the problem

 

[Ark]

I went to the shop I bought the rifle from, it is a PD trade in. The front site was made by Trijicon. They told me a standard front site adjustment tool won't work. They gave me some punches and showed me how to adjust it

Neat. I haven't seen those personally.

 

[bloodandgutsmurphy]

Is there any sign that the front sight has been changed?

I know that there are 2 different size railed gas blocks, one is rail height, and the other is low profile once I had a guy bring in his ar and had the same problem as you, his problem was he had a rail height block, and a front sight for a block height, so he maxed out his adjustment and was still shooting low.

Now if you have the fixed front “triangle” sight, this won’t be the problem

I don't know which version I have. Will take some pictures tomorrow

 

[Gabriel]

Heli-coil

They're pretty easy to install also, but you might run into problems with the front sight detente.

 

[Gabriel]

Is there any sign that the front sight has been changed?

I know that there are 2 different size railed gas blocks, one is rail height, and the other is low profile once I had a guy bring in his ar and had the same problem as you, his problem was he had a rail height block, and a front sight for a block height, so he maxed out his adjustment and was still shooting low.

Now if you have the fixed front “triangle” sight, this won’t be the problem

The 6940 does not have a railed gas block or the standard "triangle" sight.

 

[shootersix]

The 6940 does not have a railed gas block or the standard "triangle" sight.

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Ah ha! Then my comment stands, if the sight has been changed, it could be the wrong height!

 

[88E30M50]

Perhaps it's stripped out and no longer adjusting properly.

That was my first thought as well.