18mm Front sight threads

[mao0720]

Anyone know what the standard thread pattern is for an 18mm match rifle front sight? I want to confirm before I start a project. I believe it is m18x0.5. If anyone could verify that would be great! Thanks,
Mason

 

[Doug Beach]

The 22mm are .5 pitch.
Thread an aperture in about one turn. Measure the whole unit, front to rear, including the aperture. Use a sharpie to make an index mark, and screw the aperture in as many full turns as you can. Stop on the index mark. Measure the whole unit again. Divide the difference by the number of whole revolutions. Ta-da!

 

[Twicepop]

Is that 18MM, that measures out to over .070" or around 23/32nd".

 

[mao0720]

yes 18mm. I don't have an 18mm front sight in hand to be able to confirm myself, other wise I would measure. Good idea, Doug, to measure the difference in overall length on an iris over a defined number of revolutions.

 

[akajun]

Iirc it’s 18x1
I actually think I have a tap for that when I made a fsb for anshutz irises

 

[mao0720]

Iirc it’s 18x1
I actually think I have a tap for that when I made a fsb for anshutz irises

Would you mind double checking for me? I’m looking to make a front site for my Finnish m28-76 match rifle so that I can use standard front sight apertures and accessories. If your interested in selling it, I might be interested in the tap.

 

[akajun]

Ill look around this evening, but IIRC it was not hard to find or expensive. Ill let you know.

 

[Doug Beach]

It’s not going to be m18x1, or we aren’t talking about the same thing.

 

[mao0720]

I found a thread on BR central they seems to confirm that it is m18x0.5. I’ve got an anschutz iris on the way that I’ll be able to measure and confirm.

 

[dc.fireman]

yes 18mm. I don't have an 18mm front sight in hand to be able to confirm myself, other wise I would measure. Good idea, Doug, to measure the difference in overall length on an iris over a defined number of revolutions.

I have several I'm not using - I can send you one if you like?

 

[Walt Krafft]

I checked one this morning and it is M18x0.5.

 

[mao0720]

I have several I'm not using - I can send you one if you like?

Thanks dc, but I just ordered an aperture clamp.

 

[mao0720]

I checked one this morning and it is M18x0.5.

Thanks Walt!

 

[dc.fireman]

Thanks dc, but I just ordered an aperture clamp.

Okie doke. The offer is there. I have several 18mm front sights that I used to use before switching to the 22mm versions.

-tc