AR Irons Windage Accuracy

[Ericpwp]

How "on" is your AR in regards to windage?

At, say 100 yards, how close to the center line of the rear site is zero?

I am turning a budget upper into a dissipator.
Pinning the FSB, I shifted it about .025" from dead on. It is putting me off about 4.5 moa, about 9 clicks.

I used this calculator to figure that out: Sight Correction Calculations

I'm I being too picky, or are your ARs zeroed at or near the center line?

I prefer shooting irons, but I don't want to go OCD over it. I only put in one taper pin at this point, and have some oversized ones, so I have some wiggle room.

 

[Chase515]

I zeroed my aimpoint on my last build to 25 yards. Then went back and cowitnessed the sights. Might get strung out for that but it worked and was easy. Neither matters as long as you put the rifle in vise, I use a v block sand bag rest.

 

[Sigblitz]

Are you using a dummy sight up front and a shaved down gas block in the normal location? If the gas port is up front, you'll lose pressure. This will affect accuracy and jam up your gun. If that's all good, I would have the rear sight adjustable.

 

[Sigblitz]

An ar should be pretty straight up to I'm going to say 160 yards. Match your ammo to your barrel twist. There's a chart for that. A front brace helps a lot. Keep your thumb forward so the webbing on your hand doesn't move when you pull the trigger. Breath out when pulling the trigger.

 

[Sigblitz]

If there's play in the barrel pin, the barrel could have rotated when tightening down the barrel nut.

 

[Sigblitz]

I'd check first if the barrel is twisted. Don't move your gas block up front. Shooting style. Upper and lower fitment. Correct ammo. I'm guessing twisted barrel.

 

[nipprdog]

13 more to go

 

[Ericpwp]

I zeroed my aimpoint on my last build to 25 yards. Then went back and cowitnessed the sights. Might get strung out for that but it worked and was easy. Neither matters as long as you put the rifle in vise, I use a v block sand bag rest.

That's not a bad idea!


It is a carbine length gas system, with a dummy fsb at the front. I did not take the barrel off, so it did not move at the nut.

 

[ol' Huff]

I can't fix this thread, Zavala, the derp is too thick for me to get the edge of my shovel in.

 

[Ericpwp]

Oh come on, put your back into it!

Windage on your AR, does it zero on the center line?

 

[JJFII]

How "on" is your AR in regards to windage?

At, say 100 yards, how close to the center line of the rear site is zero?

I am turning a budget upper into a dissipator.
Pinning the FSB, I shifted it about .025" from dead on. It is putting me off about 4.5 moa, about 9 clicks.

I used this calculator to figure that out: Sight Correction Calculations

I'm I being too picky, or are your ARs zeroed at or near the center line?

I prefer shooting irons, but I don't want to go OCD over it. I only put in one taper pin at this point, and have some oversized ones, so I have some wiggle room.

Ok you pinned it in place and you are now off my 4.5 inches at 100 yards. This is with both front and rear at zero. The reason I say FRONT at zero is because there is a trick to shave one side of your front post... then when you look down to align the post in your rear peep, you shift the post slightly to one side... you can easily make up that 4.5 MOA with a shaved post.

Old tricks still work.

 

[natdscott]

Ok you pinned it in place and you are now off my 4.5 inches at 100 yards. This is with both front and rear at zero. The reason I say FRONT at zero is because there is a trick to shave one side of your front post... then when you look down to align the post in your rear peep, you shift the post slightly to one side... you can easily make up that 4.5 MOA with a shaved post.

Old tricks still work.

Dunno about that.

That amount of "shaving" would leave him with about a 0.045-0.050" front post. That's pretty small, in my experience.

A better solution (the best) is to drill/drive those GD pins out, remove that FSB, and put a JP clamp-on FSB in it's place. Then the rifle can just be zeroed like it should be...rotate the front base.

None of the above should be construed as an endorsement of actually doing this on a blaster rifle...

 

[Clay Pigeon]

I can't fix this thread, Zavala, the derp is too thick for me to get the edge of my shovel in.

That's the reason for pointed shovels and foot steps...

 

[Ericpwp]

I am thinking shaving it is out. I already have a thin front site on it, and I might need to zero for a different weight bullet. Thanks for the suggestion though.

So we have a vote for a reinstall. I only drilled one side in case this happened.

 

[ol' Huff]

If you ask a question about shooting irons, then I would encourage you to listen to the advice of someone who can cite things like "President's Hundred" "A2 Service Rifle High Master" and "1,000 Yards A2 Service Rifle Master". In laymen's terms, those words are how you say "expert on the use of iron sights on ARs". Don't let the derp get deeper, it only gets harder to dig out later on.

 

[Ericpwp]

I'm all ears. Thanks in advance.

 

[ol' Huff]

I'm all ears. Thanks in advance.

Read the other posts. Nathan Scott posted your solution already, and you will find all those words I put in quotes (except the last bit) in his tag line. Ignore the other solutions offered.

 

[Ericpwp]

Got it. I missed the sig line. Thanks.

 

[JJFII]

Dunno about that.

That amount of "shaving" would leave him with about a 0.045-0.050" front post. That's pretty small, in my experience.

A better solution (the best) is to drill/drive those GD pins out, remove that FSB, and put a JP clamp-on FSB in it's place. Then the rifle can just be zeroed like it should be...rotate the front base.

None of the above should be construed as an endorsement of actually doing this on a blaster rifle...

It does leave a small post, but it works if you are not going to re-pin the FSB.

 

[HK Guy]

I wouldn't be shaving anything. That said I've had some that were a click or two off center, not big deal. I had another one what was way off, almost to the end but it still zeroed. It bothered the heck out of me. After a bunch of research I found that if it zeroed it was in spec, but it still bothered me. One of the big name manufactures said that you could pound on the fsp to move the zero the way you wanted. It was a long time ago, but I think I knocked out the fsp pins and maybe filed / ground on them a little. Anyhow it went back together and the zero was much better.