ar 15

[Josef]

I recently bought an ar15 used. I'm having a bad time getting it sited. I trained and used an m14. Best I can figure out is the dude used needle nose pliers to adjust the front site. Does anyone know if I can just unscrew the front post and replace it or do I need to replace the whole front site. I have the adjustment wrench.

 

[trapperdrew]

I believe if it is the standard front site you can just replace the pin.

 

[Josef]

Thanks very much. I've just had a terrible time finding one on amazon etc. They all want to sell me the whole site.

 

[Eray]

Thanks very much. I've just had a terrible time finding one on amazon etc. They all want to sell me the whole site.

Try www.brownells.com.

 

[BCrouse]

If you want to buy it through Amazon, try searching "ar front sight post"

 

[trapperdrew]

Try www.brownells.com.

+1

They have everything.

 

[skeets]

Josef,, sometimes we need to go back to the beginning and start all over again,, I know I did ,, this is an old one but it might help you get back on track

https://www.youtube.com/watch?v=j5QCGWYfHWk

 

[car compulsive]

My AR came without sights. I currently have a Vortex red dot and Vortex flip away 3x magnifier. My Marine Corp vet son told me to put some backup sights on the gun. I put a set of Magpul flip-up sights on a few weeks ago. They co-witness with the red dot. That said, I just ordered a Nikon M-223 4-16 scope for longer range use.

Here's the current setup.

 

[Fro65]

You can buy replacements of many different widths etc.

Be advised, as you back the sight post all the way out, there is a tiny spring and detent pin under it.

Just two of the many AR parts that have a knack for vanishing.

 

[Josef]

Thanks skeets for the film, I've watched many but this feller actually knew what he was talking about. I had the gunsmith add a utility tactical low profile flip up rear site. He also installed a model no:scp-ds3039w red dot green dot scope and it's supposed to cowitness with the iron sites. He left the front site as it was. I don't ever see myself shooting beyond 100 yards. I read that if I zeroed my rifle at 50 meters that it would be on at 100 meters???

Right now the front site is depressed all the way and I'm still shooting about 8 inches low at 50 meters. Also when I adjust the front site, the windage changes making me believe the post is bent. I'm using the large rear aperture. I consider myself a fair shot.
There are many different front posts, I'm leaning toward a some of the more exotic ones, fiber optics etc unless someone can tell me why not.

 

[windzer]

Josef is this the standard A frame front site that's pinned to the barrel or is it mounted to a rail or gas block. post a pic will help us out. I've built quite a few ars I've seen a lot of goofy things people have done on ars and blame it on something being bent or broke when they totally have the wrong part on there

 

[Dalroo]

Not sure if anyone else experiences this, but I have, as well as a few friends with similar weapons. On lighter barreled ARs, after a handful of shots, it is pointless to keep trying to zero in. I have to run a patch, and let the barrel cool down before going further. No expert - just my observations.

 

[Josef]

josef is this the standard a frame front site that's pinned to the barrel or is it mounted to a rail or gas block. Post a pic will help us out. I've built quite a few ars i've seen a lot of goofy things people have done on ars and blame it on something being bent or broke when they totally have the wrong part on there

 

[windzer]

Yea I would definitely replace that front site post she looks kinda dinged up. Brownells normally has those they r good to deal with. Also dont forget the arrow on that front site that says up u turn it that direction to make the bullet go up on the target.and if for some crazy reason the a frame part of the site is bent your out of luck and you will have to go with a different gas block because those a frames don't interchange from barrel to barrel each one is drilled and staked to that barrel and no other will work right and be accurate. I hope this helps good luck

 

[MaleHoe]

Thanks skeets for the film, I've watched many but this feller actually knew what he was talking about. I had the gunsmith add a utility tactical low profile flip up rear site. He also installed a model no:scp-ds3039w red dot green dot scope and it's supposed to cowitness with the iron sites. He left the front site as it was. I don't ever see myself shooting beyond 100 yards. I read that if I zeroed my rifle at 50 meters that it would be on at 100 meters???

Right now the front site is depressed all the way and I'm still shooting about 8 inches low at 50 meters. Also when I adjust the front site, the windage changes making me believe the post is bent. I'm using the large rear aperture. I consider myself a fair shot.
There are many different front posts, I'm leaning toward a some of the more exotic ones, fiber optics etc unless someone can tell me why not.

NO, don't believe that.

If you zero at 50 yards, you will be about 2 inches high at 100.

But I do like a 50 yard zero for my AR's except the ones with am ACOG scope, those I zero at 100.

Back to the 50 yard zero and why I like it. Zeroed at 50 will mean you can aim right on and never be more than 2 inches high or low out to around 250 yards.

Rather than type more, here's a trajectory chart with 3 different popular zero yardages. It explains it better anyway.

And to your last paragraph, a regular steel sight post is all you need. If you are 8 inches low at 50 you will need to turn the front sight post down to bring the barrel up.

I may have missed it but what do you have as your rear sight?

 

[Josef]

NO, don't believe that.

If you zero at 50 yards, you will be about 2 inches high at 100.

But I do like a 50 yard zero for my AR's except the ones with am ACOG scope, those I zero at 100.

Back to the 50 yard zero and why I like it. Zeroed at 50 will mean you can aim right on and never be more than 2 inches high or low out to around 250 yards.

Rather than type more, here's a trajectory chart with 3 different popular zero yardages. It explains it better anyway.

And to your last paragraph, a regular steel sight post is all you need. If you are 8 inches low at 50 you will need to turn the front sight post down to bring the barrel up.

I may have missed it but what do you have as your rear sight?

I'm using a utg low profile flip up rear site which has windage adjustment only.
With the front site fully depressed I'm still hitting 8 inches low at 50 yards.

 

[MaleHoe]

Could you post a picture of the rear sight?

It sounds like the rear sight is too low, I need to see exactly what you have to help you.

OK, never mind I see now you said it's a UTG.

I'll be back, just stopped mowing for a quick cool down and a drink. (of water)

 

[Josef]

Once again, I can be fairly dense, assuming the rifle fired all right when I bought it and then I had the rear site changed and now the best it will do is 8 inches low then common sense would be that there was a problem in the change l made which was the rear site.

 

[MaleHoe]

Josef, what rear sight was on it before?

Obviously the rear sight is the problem, but without it here in my hands it's difficult to figure out why. If it is for an AR it should be correct.

They are different front sights as far as distance from the bore. Some are longer for mounting on a railed gas block which is lower than a railed forearm. But in your case you don't have either.

It seems your new rear sight is too short.

How about giving me a measurement taken from the top of the rail right behind the rear sight to the center of the aperture. I'll check it against one of mine to see what's going on here.

 

[MaleHoe]

Approx. 1 3/8" on mine.

And just for reference I measured (roughly) the center of the bore to the top of the front sight post, it's close to 2 7/16".