Rifle Scopes Newbie trying to understand optics vs irons.

[Maestro Pistolero]

I moved this post from my own scope mounting thread, because I realized I changed topics. Hope that's ok.

Most of my limited experience is with irons, and I am used to the 50 yrd/200 mtr IBZ (for 5.56). So I had to readjust my thinking to the 100 zero for optics and the 7.62 trajectory. I just didn't 'get it' before.

Am I correct in assuming that in order to do a precision shot at extremely close range, i.e. 25 to 80 meters, I would be dialing up the elevation settings for whatever the corresponding crossovers would be?

In other words if 43.5 yards had a crossover at 220 yards, then I use the 220 yard setting for the 43.5 yrd shot, correct?

This may have no practical use, but it helps me understand the way things work. Practically speaking, if I knew I was working at CQB range, i would "set it and forget it' at something close to a battle zero, right?

After 100 yards, with a 100 yard zero, I am only dealing with drop and wind. no more crossover to think about.

Am I getting this?

 

[diriel]

Re: Newbie trying to understand optics vs irons.

The best answer I can think of is JBM ballistic calc program. Type in the info for what you are used to (5.56 ?), then type in the info for the 7.62 and compare the ballistics. I think this will help you to "visualize" what you are working on. It seems like you have it figured out.

http://www.jbmballistics.com/ballistics/calculators/calculators.shtml

Have a good one,
Gary

 

[vman]

Re: Newbie trying to understand optics vs irons.

Maestro let me answer your question in a simple way

When it comes to rifles and scopes all you need to care about is:

- Set your zero for your scope at a practical range. 100 yards is common but if your shooting only to 600 yards and thats it, then a 600 yard zero is more practical. You be the judge but 100,200 and sometimes 300 yard zeros would be your most common settings with 100 being way on top of the list.

- Work out your drop chart and base it on deviations from zero... ie 100 yards = zero, 200 yards = x amount of drop (x clicks), 300 yards = x amount of drop and so forth. Using a ballistics calculator takes out 95% of the work for you.

- Work out your wind based on deviations at full value wind ie 3 oclock and 9 oclock positions, for different wind speeds. Familiarise yourself with wind values at different positions. This is important. 12 o'clock (head on wind) = no value, 1 o'clock = half value, 2 o'clock = 7/8th value and 3 o'clock (Side wind) = FULL value.

So when you shoot your rifle, you determine the range and the wind. You either modify by adding elevation on your scope and adding in wind by shooting into the wind or dialing it in on the wind knob/turret. OR. You can just "hold over", so not touching knobs or anything, just aiming above a certain height and holding to the side a bit so that the bullet deviates to hit your target.

Thats it... Keep it simple stupid. Thems the extreme basics now go out and learn more about them.

 

[gugubica]

Re: Newbie trying to understand optics vs irons.

Maestro...you have it correct.

For a shot less than your 100 yard zero, you are dailing up.

And yes, this will relate to a shot at distance.

 

[bignada]

Re: Newbie trying to understand optics vs irons.

You are correct that at some point from the barrel your scope is "zeroed" at the distance zeroed for and at that close-range where bullet is still arching upward in its trajectory.

Battle-sight zero takes care of most guess-work unless you are trying to thread a button. Might look at some velocity/trajectory tables. If you have a loading manual you can plot a trajectory curve with graph paper. If you have a duplex reticle, might experiment at close range by using the top junction of thin/heavy stadia lines of your reticle as an aiming point for close range; or even use it zeroed for 100yds and then use the center reticle for a 250 (or whatever turns out to be) to 375yd battle-sight Zero...

All sorts of ways to use your scope reticle. Only benefit scope has over decent aperture iron-sights at same distance is the simplicity of aligning one aiming point (reticle) rather then 2 (aperture & blade). Many see the primary function of the scope as an optic enhancement or stand-in for a spotting scope. Target identification at distance is for sure enhanced, but to what degree must the target rendering be optically "perfect"? Turret movements and reticle alignment on the square must be perfect, for best results; but if Service Rifle and HighPower shooter can deliver sub .5moa groups at 600 and 1000yds what purpose does optical image excellence really serve?