Ranging with Front Sight Post?

[M4Fundi]

Is there a general rule of thumb for ranging with the front sight post on an M4?

I just figured that the post was so many inches high/wide at certain ranges or that there was a standard philosophy for using it for ranging.

[Failure2Stop]

Generic rule- if the shoulders of the enemy are as wide as the front sight you are approx 300 meters away. 2/3 the size of the shoulders (about chest width) is approx 200 meters, and equal in width to the head is approx 100 meters. This was for the A2, with a fixed stock and 20" barrel. Reducing the front sight distance from the eye, such as going to an M4 sight radius or collapsing the stock, will make the front sight appear larger in relation to the target at the same distance.

Ranging with iron sights is a bit of a fallacy though. Basically, since the eye can only focus on one thing/distance at a time, either the front sight or the target will be out of focus if one is focused on. This makes the whole front sight relationship/distance estimation a bit hazy and very hard to do with any degree of accuracy in actual use.

[M4Fundi]

Thanks F2S

[gfunx2000]

Is there a good way to learn/practice range estimation? I've finally found somewhere where I can go and shoot out as far as I'd like to. I was out with a friend this weekend and we were making good hits at 600M after we fine tuned our holdoffs. So I know I can shoot out to that range, but its a KD range and I'd really like a way to work on being able to accurately estimate distances so that I can be effective without the benefit of shooting from a set yd line.

[esskay]

Is there a good way to learn/practice range estimation? I've finally found somewhere where I can go and shoot out as far as I'd like to. I was out with a friend this weekend and we were making good hits at 600M after we fine tuned our holdoffs. So I know I can shoot out to that range, but its a KD range and I'd really like a way to work on being able to accurately estimate distances so that I can be effective without the benefit of shooting from a set yd line.

Obviously utilizing reticles/etc are a nice way to range, and you could practice it to get better/quicker.

But to try to get better at simply eyeballing distance, the best thing I've found is to grab a rangefinder, look at stuff, guess the distance, laze it and see how close you were...

[Boss Hogg]

A lot simpler if you just use the 65 MoA circle on an EOTech......

[gfunx2000]

Could you elaborate on using the 65 moa for ranging

[Failure2Stop]

If you have a need for precision shooting past 300 meters, you have a strong need for precise distance estimation.

The best methods for this are a laser range-finder and a mil-dot reticle.
Mil-dots are an easy way to estimate range, and the laser range-finder is a decent way to get fairly precise distances, though they have some issues with brush, dust, grass, and aim.

The reason that distance estimation needs to be precise is that overestimation by even 30 or 40 meters at 600 meters can result in huge differences in POI, and a 30 meter difference can be very hard to see without the right tools.

[esskay]

Could you elaborate on using the 65 moa for ranging

It's rudimentary ranging. Basically, 65MOA is 65" at 100 yds. That's 5 ft 5 in, so you can sort of quickly guesstimate range by comparing the height of the threats to the circle.

Someone here made some diagrams:
http://www.xdtalk.com/forums/ar-talk...ion-chart.html

As in the linked diagram, if a person standing upright takes up the entire circle, they're about 100 yds away. If they take up half the circle, then they're about 200 yds away, and so on. And if you have a sense of typical height of combatants vs the 5'5" benchmark, you can sort of shade one way or the other.

[Failure2Stop]

If they take up half the circle, then they're about 200 yds away, and so on. And if you have a sense of typical height of combatants vs the 5'5" benchmark, you can sort of shade one way or the other.

If you can convince the guy you want to shoot at to stand straight up while you aim in, it works ok.

However, ranging out to 200 yards isn't too much of a concern given the relatively small amount of drop difference between 100 and 200 yards. Ranging past 300 is really where distance estimation on live threats will make a difference, and at those distances with guys that don't want to get shot, the 65 MOA ring is pretty much useless.