Just a beginner who has a few questions: I just had my Leupold VX3 4.5-14 x 50LR on my 300 ultra mag zeroed the other day. I have M1 windage and elevation turrets on the scope.
My questions are:
1. Do I reset my 0 by using the allen key to re-adjust the elevation knob/zero mark?
2. With the load I am shooting, I have an estimated 41.16" inches of drop at 500 yards pushing a 200 grain accubond. Theoretically, to adjust for this shot with 1/4" MOA scope adjustments, would I calculate the number of clicks by dividing 41.16" /.25"?
3. If my assumption is correct in question #2, would I have enough adjustment in my scope to do this, or would I have to aim my crosshairs higher to compensate for this type of shot?
I am really confused and am looking for clarification.
Sorry for such dumb questions, but I am just a beginner. Thanks for the advice in advance.
In short... no! As you go farther out the adjustments change with the length of distance. Your scope will have more than enough to get you to 500yrds.
Here is some quick math:
100yrd= .25" per click
200yrds= .5" per click
300yrds= .75" per click
400yrds= 1.00" per click
This trend continues as you extend your range. 1/16" = 25yrds. per click. That is why when you try to adjust for shorter yardages you need to far exceed the number of clicks per inch. As you go out the number of clicks decrease. At 1000yrds one click equals 2.5". Hope this helps.
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you have to remember the adjustments are in minutes of angle. each click is 1/4th of a minute of angle.. this equates to very close,and for practicle application, a 1/4 of an inch at 100 yards. so one MOA (minute of angle) is one inch at 100 yards. an easier way for some is to break down how much you have to adjust at 100 yards to get the desired results. in your case to move the impact say, 40 inches at 500 yds, is the same as moving it 8 inches at 100. the adjustment would be 8 MOA up. another scenario would be you have a 32" drop at 475 yards. just making up numbers. you divide 32 by 4.75, this gives you 6.73. so move the scope up 6.75 minutes of angle. of course this only works if your scope is moving in exact moa adjustments. but that's another post.
If you have M1 turrets you should be using the dial indicator rather than counting "clicks". its way faster and less room for error. Once you have your rifle set at zero and you've adjusted the dial marks to read zero also, just dial up your correction. Its also alot easier to print your drop sheet or set up your ballistics program to give your come ups in MOA rather than inches. Hope this is usefull.
The answer to your first question is YES. There should be a single set screw on both the windage and elevation turret. After you have zeroed your scope with the load you plan on using then just loosen the screw and turn the turret to zero and re-tighten (not overly).
The short veritcle lines under the "0" indicater (and visible from behind the scope)are called index lines or base lines. Remember what line yours is on after you have zeroed the elevation turret (also called slipping the scales) and this is your initial zero, example: You have zeroed the scope and slipped the scales and have a zeroed base line of three. If you want to adjust for a 17moa elevation adjustment, then go to BL4+2 (since you have 15moa per turret revolution). This, or at least remembering what base/index line you are zeroed for, can save you a lot of head ache in the future by making sure you have returned back to zero after a shot or series of shots.