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qosmio
09-21-2011, 12:02 AM
okay so i got a pretty good deal on a leupold mk4 LR/T with mil dot reticle. each click is 1/4 moa. this might sound like a stupid question and i've searched all over the internet but i still don't understand how to do adjustments on the scope. all this calculation stuff is driving me crazy and im sure someone has the simple answer to this. i've taken it out to the range but the closest range to me only goes out to 100 yds. i haven't shot anything beyond that so i haven't been able to really use the scope.

so my question is, the scope it zeroed at 100yds, say im walking along and i spot a deer that is about 300 yds away, instead of just using the holdover to shoot, how do i adjust for distance? like how many clicks would i have to go to get the scope set at 300 yds..?

baz152
09-21-2011, 12:11 AM
You have to dope your rifle first. The only way to do that accurately is to shoot your rifle at 25 yard increments and record how many minutes you had to come up. You do that for every 25 yards out you plan to ever shoot your rifle then you have the dope to that gun. You have to make sure to always use the same ammo and keep in mind that the environmental conditions can have an impact at range.

Now that you have the dope you need to know the size of your target to do range estimation with the mils, that is a little more complex and is better learned by reading a book.

qosmio
09-21-2011, 12:21 AM
i've been doing a lot of reading. read over the manual many times, read stuff online. i was trained how to shoot with iron sights so this scope thing is new to me. it's just confusing. and having a range out here going past 100 yds would help but it's about a 2 hr drive.

it's mounted on a rem700 xcr tlr .308 btw........

skkeeter
09-30-2011, 7:45 AM
If you can't actually shoot your rifle out to 300, then this will get you in the ballpark.
http://www.jbmballistics.com/cgi-bin/jbmtraj-5.1.cgi

Just please don't try to go hunting not knowing where your shots going to hit. As the previous guy said, environment plays a large role on bullet impact at distance. Buy yourself a logbook, or make your own,
http://www.calguns.net/calgunforum/showthread.php?t=193106

This way you can get you dope settings for your rifle on paper. Best way to know how much to adjust your scope is go out and shoot the thing, a lot!!!

rero360
09-30-2011, 8:10 AM
There is a formula out there that you can use to convert MOA to Mil and vise versa, however I can't think of it off the top of my head. But I do know that 1 mil= 3.438MOA and 1 moa= .2908Mils

While all that math is fine and dandy when you are at the range and you have the time to pull out your calculator and all that, in the field you are better off doing holdovers. Basically zero the rifle for a set range, then find what the bullet drop will be at different ranges in MIL that way you can just use the reticle to make the holdovers without finger banging the turrets with a trophy buck taking his time to move out of your line of sight.

Oh yeah, since that scope is a second focal plane model, unless you got one of the new first focal plane ones, you will have to keep it at max magnification to use the reticle accurately, or you can test it at half power to see if it will accurately subtend, needing half the holdover as at max (don't trust the markings on the scope as they are never accurate) plus all this is not a concern with a first focal plane scope where the reticle matches the turrets.

Clear as mud, I know, but if you are comfortable with trig and some other basic math having a mil/moa sfp scope isn't the end of the world. but you do need to get to the range and actually shoot at various distances at different magnification settings and record the findings as accurately as humanly possible.

FLIGHT762
09-30-2011, 8:46 AM
If you can't actually shoot your rifle out to 300, then this will get you in the ballpark.
http://www.jbmballistics.com/cgi-bin/jbmtraj-5.1.cgi

Just please don't try to go hunting not knowing where your shots going to hit. As the previous guy said, environment plays a large role on bullet impact at distance. Buy yourself a logbook, or make your own,
http://www.calguns.net/calgunforum/showthread.php?t=193106

This way you can get you dope settings for your rifle on paper. Best way to know how much to adjust your scope is go out and shoot the thing, a lot!!!

Learn how to use the JBM ballistics data to make up a range card for your rifle. It take a little while, but it works. Learn the input data. Hook up with someone who is familiar with range range shooting to help you out. It will make it easier for you.

Your range card will get you very close, but you actually have to shoot at the distances and record the come ups. Start thinking the come ups in MOA instead of individual 1/4 min. "Clicks". If you try to count clicks, it will make you crazy, especially the farther out you go.

Here's a couple of articles:

http://demigodllc.com/articles/practical-long-range-rifle-shooting-equipment/

There's a lot of information on the net. Once you get out and actually shoot at long distance, you will start to get it. Try to find a mentor in your area. If you learn to understand the basics it's not difficult.

You have to pick an accurate factory load (unless you reload) and stick with it. You can't change bullet weights / styles and have the trajectory be the same. If you want to use your set up for hunting out to 400 yards or so, it will be pretty easy to make up a range card with your come ups in MOA.

Here's a basic ballistic calculator. it can give you come ups in 50 yd. increments. Very important to input the proper information, bullet, velocity and sight height. most of my bolt L/R rifles have a sight height of 1.8" to 2.0". It can be some where to start. The JBM program can get a bit overwhelming to start.

http://bisonballistics.com/point_mass_calculations/new