Question about zeroing

[benne911]

Ive been reading the manual on zeroing my bushmaster m4a3. One thing that I dont understand and seems odd iss that to zero it in you have to lower the sight assembly all the way down and then one click up to the 6/3. Now why would you want it all the way down because you would have no room for adjustment in the field when shooting at different distances??:confused:

[Funkenstein]

If you are talking about your front site post, bringing it down will force you to aim higher, which is something you need to do if you are at close range due to the barrel being lower than your point of aim.

I would site it at whatever range you plan on shooting from the most and then compensate at closer ranges by looking over your sights and aiming higher.

[benne911]

I am going to zero it at 25 yards. But when watching bushmasters instructional video they say to lower the elevation know until onee click before the last when it is at 3/6. Next step was to shoot then make elevation adjustments with the front post. adjust windage, shoot again and youre sighted in. But with the elevation knob one click to the end, how can you have room for future adjustments, say if you have to adjust to 50 yards?

[C-grunt]

Standard AR sights have a low end zero of 300 yards. When you turn the drum you will see marks for 4 through 6 hundred yards.

[lifebreath]

Stickies ... Your friend.

https://www.m4carbine.net/showthread.php?t=65679

[careboy]

If you are talking about your front site post, bringing it down will force you to aim higher, which is something you need to do if you are at close range due to the barrel being lower than your point of aim.
http://www.primeaffiliate.com/track/images/22.gif
http://www.canadablackberry.com/imgs/images/2.tod.gif

[Belmont31R]

Christ...


Elevation is adjusted with the FSP. Windage is adjusted with the rear sight.


The 6/3rds thing is because in the military you zero at 25M, and with a 25M zero you would be shooting way high at 200+. So you zero at 25M, and then AFTER that you adjust to 6/3 +1. That brings the zero closer to like a 50M zero. The mil isnt going to have a bunch of dumbasses range walking out to 100M when 25M is so much quicker.


If it were me I would zero the irons at either 50 or 100. Either will give you a zero that would allow you to put a properly centered FSP on a noggin from about 20 yards to 250 and hit said noggin. Under 20 yards aim a little higher or basically cover the noggin up to the forehead with the FSP and if you're THAT close just aim over of the sights or use instinctive shooting. Try some 2 yard to 15 yard torso targets while instinctive shooting and see how you do. You really don't need to sit there and sight in with irons on a target 10 yards away.

[ST911]

There are a number of threads on the merits of the various zeros, and how to achieve them. Most will advocate a straight 50 or 100yd zero. Ignore the elevation wheel.