Can some explain my sniping question in a noobish way?

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LloydXmas250

New member
Alright. So in the next couple of months I'm going to be getting a tactical scope with turret target knobs. Right now I'm leaning towards the Millet TRS-1 w/ .1 Mil adjustments. I've studied how to use Mildot scopes and even done some practice games where I figure out range and then adjust the mils/MOA to the correct elevation. In the game, there's a chart that tells me what to raise my mils/MOA to to compensate for bullet drop. In reality, what do you use? Where do you get a chart like this. I found the Mildot Master that shows you target range and bullet drop but how does that work with differing calibers? Basically, I'll be shooting .223 long distance, for fun and maybe for competition later. How do I know how many mils to raise on my elevation for each distance? What chart or tool will let me do this? Thanks for the help.
 
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Jimro

New member
Start making your own data book, that records your adjustments for the range and conditions of each shot you put down range.

That way you will build your own data set for your rifle and load (or loads).

Also you can play with a ballistics program to print out custom tables for drop and windage.

Jimro
 
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LloydXmas250

New member
Once I know my bullet drop for each range, how is that calculated into mils. I feel like this is a really simple thing that I'm just not understanding for some reason. I guess I can try and make up an example (probably not realistic). Let's say my target is 350 yds and my .223 drops one foot in that distance. Is there a tool to measure how much that one foot is in mils at 350 yds? Or is that something that I need to know converting mils into inches and feet at specific distances?
 
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azredhawk44

Moderator
MOA is minute of angle.

There are 360 degrees in a complete circle. At 100 yards, an arc of 1 degree is about 5 feet wide.

A degree has 60 minutes of angle to it. Or, 1 minute of angle is 1/60th of 1 degree.

That makes an MOA to be 1" per 100 yards. In reality, the number is about 1.04 and some change, but for most folks 1" per 100 yards is just fine.

1 MOA = 1 inch per 100 yards.

Or... 1 MOA = 2 inches at 200 yards.

Or, 1 MOA = 3.75 inches at 375 yards.

So, if you need to adjust down 18 inches at 600 yards, you need to come down 3 MOA (@ 600 yards, 1 MOA = 6 inches. 18 inches divided by 6 gives you 3 MOA).

Mils are 1 meter of angle at 1000 meters. Or, 10cm at 100 meters.

Roughly computed, 1 Mil is about equal to 4 MOA, I believe (10cm = ~4 inches, 100 yards is roughly the same as 100 meters... I suspect the real number is closer to 3.8 or 3.9 but this should give you an idea).

So, at 500 meters you need to come down 150 centimeters, you need to come down 3 mils (1 mil is 1 meter per 1000 meters, or a half meter (50cm) at 500 meters... 150/50 gives us 3 mils).

ETA:

From Wikipedia (http://en.wikipedia.org/wiki/Angular_mil):

1 mil = 3.43775 MOA

So, a scope with 1/10 mil adjustments is roughly 0.343 MOA per click. Scopes with 1/4 MOA adjustments are roughly 0.25 MOA per click. You get finer control over the adjustment with a 1/4 MOA scope than you do with a 0.1 mil scope.
 
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zoomie

New member
First thing is to eliminate inches or cm from your brain. Those are linear measurements and are not useful for adjusting elevation or windage. (Of course they are important for reticle ranging, but that's a different topic.)

You need to think in angular measurements: MOA or MIL. If you've got a mil reticle and mil turrets, than that choice is already made.

For starters, go to this site: http://www.jbmballistics.com/cgi-bin/jbmtraj_simp-5.0.cgi

Start playing with that. That'll give you a rough wag or your bullet trajectory - in MILs. It'll tell you that you need .4 MILs for X yards, 1.2 MILs for X yards. The inches of drop are irrelevant.

Then go to the range and set up targets at as many distances as possible. Shoot at those ranges and compare the actual ANGULAR adjustment required to hit your bullseye to what was predicted by JBM. Keep notes of the adjustment required to hit your target at various ranges. You don't care if you had to come up 15" at 500 yards. You care that you had to come up 0.9 MIL. Programs like Exbal will help you mesh the actual and predicted performance, but you can look at those later if you choose to.

A good post on the basics:
http://www.calguns.net/calgunforum/showthread.php?t=199178
 
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LloydXmas250

New member
Definitely more understanding. Like I said, I had been reading this stuff and doing exercises but I was just reading mil and MOA adjustments off a chart so I wasn't getting the full experience with them. With that site and eventually going out I'm sure it will only be a matter of time before it becomes second nature. Now if you don't mind another question, how far can I realistically take .223? More for fun rather than hunting.
 
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azredhawk44

Moderator
To put a hole in paper, 1000 yards.

But, you have to have the right bullet in the right barrel with the right rate of twist.

I hear that 6.5:1 twists are popular with the 80 and 90 grain sierra match bullets, when shot from AR's. 7:1 is the match default for most CMP and High Power shooters at 600 yards.
 
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TargetTerror

New member
[quote I'm liking this site: http://www.jbmballistics.com/cgi-bin...j_simp-5.0.cgi
but how do I change from MOA to mils? I'm missing that option. My scope will be Mildot with .1 mil adjustments.[/quote]

You have absolutely everything you need right there. JBM ballistics is pretty much the gold standard for ballistics software, and it's free! When you are setting up the trajectory calculation, you can have it output your drop in 2 different units. Just set it up for MOA and mils and you'll be good to go. It also has a nice little "range card" mode/page, so you just plug in your data and creates a little range card you can print out and take around with you.

Of course, all this assumes that you have accurate velocity data, so you'll need a chronograph to be closer on farther out. And remember that all software gives you various theoretical expectations - make sure you test your loads in real life to see whether they are close or not.

As for the adjustments in mils, that is perfect! Mils and MOA are just 2 differnet ways of measuring angles, nothing more. The best is to have your reticle match your turrets - then you just look at the reticle and say "ok, i'm 2.1 mils to the left," and dial 2.1 mils on your turrets. No math involved that way. It is only when you have mismatched mil/moa reticles and turrets that you run into math conversion issues.

More on the mil/moa issue here:
http://www.snipershide.com/forum/ubbthreads.php?ubb=showflat&Number=779323
http://www.snipershide.com/forum/ubbthreads.php?ubb=showflat&Number=1690363
 
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