M4 Iron Sights Help!

[AdamJaw89]

ok i am having some major issues trying to zero in my M4 flip up rear iron sight and my front sight post at 25yards. so i have some questions and any info at all would help.

1. if i am shooting high, how do i lower where the bullet impacts?

2. if i am shooting low how do i raise where the bullet impacts?

3. if i am shooting to the left how do i adjust to make bullet impact more right?

4. if i am shooting to the right how do i adjust to make bullet impact more left?

i am shooting off sandbags, also any tips on how to shoot the rifle more accurate, how should my sight picture look like when i am shooting?

this is my first M4 and i have never ever messed with these kind of iron sights before so i have no idea whats going on. please help lol i am getting so frustrated. also should i zero it at 25 yards or at 50?

 

[sv51macross]

Elevation is done with the front sight post (as you mentioned flip rear sights) and windage is gone with the back sight.the front sight post between the 'ears' is on a screw that allows it to be adjusted up and down, and all flip rear sights have some kind of adjustment wheel at the base or on the same axis as the apertures.

 

[Steve in PA]

If you are shooting high and want to lower your point of impact (where the bullets are hitting), you raise the front sight.

You do the opposite to raise the point of impact......lower the front sight.

Shooting left and want to move the impact to the right? Move the rear sight to the right.

Shooting right, need to move left? Move the sight to the left.

 

[Ryder]

Steve has it right. I always visualize this with my fingers before adjusting my sights (memory isn't so great these days).

Using a finger for the front sight one one hand and another finger for the rear sight on the other hand. With fingers aligned as sights lower the front finger. In order to bring your fingers back in line (imagining they are now locked on a gun barrel) visualize how the barrel would have to move in order to bring the sights back into alignment. You have to raise the barrel after lowering the front sight. Raising the barrel can only make the impact higher.

You can do this same thing moving the rear finger. The imaginary barrel must be moved right or left to realign your fingers after moving the rear finger right or left. Whichever way your barrel moves to realign is the direction the bullet will also move on paper.

 

[alohachris]

Google "IBSZ" and or "Santose improved battle sight zero". You'll learn all you need to know about M4 sights.

 

[Destructo6]

The front sight should be clockwise to raise the point of impact.

The rear sight shuld be clockwise to move the POI to the right.

All M4/M16 sights should work that way, unless you have an oddball.

 

[PandaBearBG]

+1 for all of the above. As for improving accuracy, sling up for a more solid position. meaning a two point sling wrapped around your supporting arm bicep nice and snug and tight. Marine Corps never wrong!

 

[halfded]

Just did the same thing yesterday. How to move POI has already been covered.

I sight in at 50 yards or IBZ. Keeps the bullet within 2 inches from 0-200 yards. Make a lollipop with the front sight post as the stick and the bullseye as the candy. Slow steady pressure on the trigger til she goes bang.

Remember this: BUIS are for just that, BU. My irons shoot about a 1/2 inch left but if I go over another click right, I'm 1/2 inch to the right. Don't expect target rifle accuracy is all I'm saying. Good groups are attainable for sure, shooting bullseyes all day might be a little more difficult.

As far as shooting off a bench, 20 round mags help a lot as they don't act like a giant bipod. Use a steady front rest (not your hand) and take the time to get comfortable behind the gun. Pull the rifle in snug but not tight to your shoulder and place your offhand (in a fist) under the end of the buttstock so it sits on top of the circle formed by thumb and forefinger. Then you just squeeze or relax your fist to raise and lower point of impact. Makes for a pretty stable rest for me, though still not as good as a rear bag. My rifle won't fit the rear bag I have unless I'm shooting birds.

+1 to using "finger sights" to jog the memory!

 

[CortJestir]

Question asked and answered, but I'll add that when adjusting any set of irons, here's a helpful phrase:

"Use the F.O.R.S." Front sight opposite. Rear the same.

IOW, move the front sight in the opposite direction you want POI to go. Move the rear sight in the same direction.

 

[Quentin]

Here's a very handy PDF you can print out - an M4 25 meter zeroing target that tells you how to adjust the sights to move your group. I assume your rear sight windage adjusts the same as the standard A2 sight.

BTW, in regard to the M4 with a carry handle - there is a slight error at the bottom when it says to set the elevation knob to 8/3, it should say 6/3.

http://ohmr.ohio.gov/forms/ohmr2444-b.pdf

 

[RyanM]

Make sure your front sight base (not the post, but the forged aluminum base) has an "F" on it somewhere. Usually the left side. The vast majority of flip-up rear sights are mil-spec height, which needs an "F" front sight base. If there is no F, you're pretty much never going to be able to get the height right without buying an aftermarket extra-tall front sight post, or swapping out the base. Or getting a "commercial" height rear sight.

 

[Quentin]

Good point, Ryan! He wouldn't be off the paper at 25 yards but this could make zeroing real frustrating. If he were using the IBZ or a 100 yard zero with the non-flattop FSB the front post would have to be unscrewed too much and flop around.