Is extreme windage adjustment unusual? Sight tool for PRI flip-up?

AR Sponsor:

[ARCHIVED THREAD] - Is extreme windage adjustment unusual? Sight tool for PRI flip-up?

Posted: 9/25/2004 7:33:25 PM EDT

I have a PRI flip up front sight on my recent build and an ARMS 40L on my flattop receiver. Today I went to zero the carbine in and I ended up need to adjust the windage almost all the way to the right to hit what I was aiming at. Additionally, a standard front sight tool doesn't work with the PRI (the shroud prevents it from doing so) where can I get a proper front sight tool?

Posted: 9/26/2004 5:59:55 AM EDT

[#1]

Just make sure your PRI is perfectly paralle to the flat top upper. Or your Windage will have be adjusted to compensate for the canting of the FLipup sight.

Posted: 9/26/2004 7:52:32 AM EDT

[#2]

so I should mover the PRI to the left? this is disconcerting to say the least... any tricks for making sure it mounted right? it looks ok...

Posted: 9/26/2004 3:33:21 PM EDT

[#3]

If you have an Aimpoint, it should be an easy fix:

Mount and zero your Aimpoint @ 50 yards......

Leave the Aimpoint mounted and switched on.....

Reset the rear aperature (using the SMALL aperature) to the center.....

Slightly loosen the set screws on the PRI and move the front sight to the right (you will not have to move it much) until it lines up with the Aimpoint dot.....

Re-tighten set screws (make sure front sight post is still in alignment with Aimpoint dot).....

Adjust front post (up or down) and rear peep (using SMALL aperature) to match Aimpoint dot....

Remove Aimpoint and attempt to re-zero the irons @ 50 yards. You should not need to make much adjustment and should be good to go.

Posted: 9/26/2004 3:53:19 PM EDT

[#4]

mo4040 pretty much covered it, but basically you need to start your windage adjust by moving the PRI with your windage adjust exactly in the middle. When you get it close, you can fine tune it with the windage adjust. There's really no other way to get it done without ending up with gross windage adjust like you had.

When I install PRIs, I use the Aimpoint trick and my calibrated eyeball

to get them close. Usually I'm within a few clicks using this method.

Posted: 9/26/2004 6:14:17 PM EDT

[#5]

dig down a page or three for thread ARMS40 excessive windage, some good explanations by the last poster. my #40L is the same way.

Edited for link:

www.ar15.com/forums/topic.html?b=3&f=18&t=202115

Posted: 9/26/2004 10:21:53 PM EDT

[#6]

how annoying... I can't even hit POA at 15 yds

Posted: 9/26/2004 10:36:53 PM EDT

[#7]

Quoted:
how annoying... I can't even hit POA at 15 yds

Don't fret, dude....I had a PRI installed on an upper and I couldn't hit the proverbial "broadside of a barn" either. Just follow my suggestion and you'll be fine, trust me. I also use the ARMS 40-L on this same upper, so I know what you are experiencing. Before long, you'll be good to go and will forget all about this BS.....

Posted: 9/27/2004 4:50:05 AM EDT

[#8]

no aimpoint here... eventually, I suppose

Posted: 9/27/2004 5:10:26 AM EDT

[#9]

If you can borrow another rear sight, center both for windage and mount the second one at the front of your flattop receiver. Get a new piece of drill rod that is just smaller than the large aperture(s). slide it through both and extend up to the front sight. Line up the sight and tighten into place. You can get very close this way, I actually have better results than slewing to an Aimpoint dot.

Posted: 9/27/2004 5:13:11 AM EDT

[#10]

Quoted:
If you can borrow another rear sight, center both for windage and mount the second one at the front of your flattop receiver. Get a new piece of drill rod that is just smaller than the large aperture(s). slide it through both and extend up to the front sight. Line up the sight and tighten into place. You can get very close this way, I actually have better results than slewing to an Aimpoint dot.

Noted in my book of tricks to be used in the future. Good technique.

Posted: 9/27/2004 9:05:39 AM EDT

[#11]

Quoted:
Quoted:
If you can borrow another rear sight, center both for windage and mount the second one at the front of your flattop receiver. Get a new piece of drill rod that is just smaller than the large aperture(s). slide it through both and extend up to the front sight. Line up the sight and tighten into place. You can get very close this way, I actually have better results than slewing to an Aimpoint dot.

Noted in my book of tricks to be used in the future. Good technique.

+1

Posted: 9/27/2004 10:47:29 AM EDT

[#12]

Quoted:
If you can borrow another rear sight, center both for windage and mount the second one at the front of your flattop receiver. Get a new piece of drill rod that is just smaller than the large aperture(s). slide it through both and extend up to the front sight. Line up the sight and tighten into place. You can get very close this way, I actually have better results than slewing to an Aimpoint dot.

thanks for the tip.. I may be able to do this..

Posted: 9/27/2004 11:14:19 AM EDT

[#13]

I just put a ruler on my flattop, and a ruler on my YH front flipup sight.

Came out dead nuts on.

Posted: 9/27/2004 4:19:34 PM EDT

[#14]

Quoted:
I just put a ruler on my flattop, and a ruler on my YH front flipup sight.

Came out dead nuts on.

what did you align? the left edge of the sight and the left edge of the upper or the center of the upper and the center of the front sight post... gosh this is frustrating....

also...still haven't heard any solutions for adjusting elevation on PRI front sight since the standard tool doesn't reach. thanks guys

Posted: 9/30/2004 5:26:21 AM EDT

[#15]

Does your PRI front sight have the half moon cutout on the top? Most front sight tools will fit this cutout okay, though I have seen a few that were too short. There are some early PRI sights that do not have the cutout. A bullt tip or the short side of a hex key work though.

Posted: 9/30/2004 5:34:01 AM EDT

[#16]

Quoted:
Quoted:
I just put a ruler on my flattop, and a ruler on my YH front flipup sight.

Came out dead nuts on.

what did you align? the left edge of the sight and the left edge of the upper or the center of the upper and the center of the front sight post... gosh this is frustrating....

also...still haven't heard any solutions for adjusting elevation on PRI front sight since the standard tool doesn't reach. thanks guys

With my setup, I could align the top of the receiver with the top of the gas block/front sight assembly.

Posted: 9/30/2004 12:08:23 PM EDT

[#17]

Quoted:
Does your PRI front sight have the half moon cutout on the top? Most front sight tools will fit this cutout okay, though I have seen a few that were too short. There are some early PRI sights that do not have the cutout. A bullt tip or the short side of a hex key work though.

erg

yes, I do have the cutout but my tool is too short

fight4yourrights: I'll give your suggestion a shot, thanks

Posted: 10/8/2004 9:49:52 AM EDT

[#18]

Quoted:
Quoted:
Quoted:
I just put a ruler on my flattop, and a ruler on my YH front flipup sight.

Came out dead nuts on.

what did you align? the left edge of the sight and the left edge of the upper or the center of the upper and the center of the front sight post... gosh this is frustrating....

also...still haven't heard any solutions for adjusting elevation on PRI front sight since the standard tool doesn't reach. thanks guys

With my setup, I could align the top of the receiver with the top of the gas block/front sight assembly.

I tried to do this and it all looks straight....
Does anyone know...can I just loosen the two allen bolts on the left side and shift the front sight base to the right a hair to alleviate this abnormality and retighten or will I have to mess with the gas tube, etc. as well or do something more involved to try to make my POA and POI the same?

Posted: 10/8/2004 1:37:11 PM EDT

[#19]

Take the screwdriver with the correct allen bit for the PRI clamp bolts to the range with you. Shoot at 25 yards, and adjust the PRI sight/gas block to center the POI while the rear sight stays mechanically zero'd. The hole inside the gas block is about twice as large as the gas port in the barrel, so you have considerable "wiggle room" to play with and still have proper functioning. HTH.

Paladin

Posted: 10/9/2004 9:36:10 PM EDT

[#20]

Quoted:
If you can borrow another rear sight, center both for windage and mount the second one at the front of your flattop receiver. Get a new piece of drill rod that is just smaller than the large aperture(s). slide it through both and extend up to the front sight. Line up the sight and tighten into place. You can get very close this way, I actually have better results than slewing to an Aimpoint dot.

Thanks for the tip!

[ARCHIVED THREAD] - Is extreme windage adjustment unusual? Sight tool for PRI flip-up?

AR-15 » Optics, Mounts, and Sights

AR Sponsor:

Warning

Confirm Action

About AR15.COM

Stay Connected

Newsletter

Contact Us