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Scope adjustments between 100m to 900m

Let me first say what a great web site and I hope someone can give me some guidance...

New to long range shooting I am looking for some indicative scope adjustments required between distances once zeroed at 100m. I have just purchased a Rem 700 action in 6mmBR with a 1:8 douglas barrel. The plan is to put a 36X weaver on nightforce 20moa bases. Short distance 100-300m shooting I am looking to use Hornady moly 75g and longer distances 400-900 Hornady moly 105g's. Also using ADI 2208 powder the equivalent of Varget.

So the real questions
Is 20moa bases enough to cover the variable ranges?
How many clicks up between 100-200, 200-300, 300-400, 400-500, 500-600, 600-700, 700-800 and 800-900?
 
So to further question this topic, I am shooting a 6.5X47L at what I think will be about 2850 FPS with 130 GR Berger VLD. I have a 20MOA base already. What MOA adjustment range will my scope need to be for me to be able to zero in at 200 yards but still be able to dial out to 1000 yards? If a scope is listed with a 35MOA adjustment range, does that mean it is 17.5 up and 17.5 down or is that not necessarily the case? Below are my drop estimates. Thanks for the help.

Range Velocity Trajectory
(yards) (fps) (MOA)
0 2850 0.00
100 2684 1.59
200 2523 0.00
300 2368 -2.27
400 2219 -4.89
500 2075 -7.81
600 1937 -11.04
700 1805 -14.62
800 1680 -18.57
900 1562 -22.96
1000 1452 -27.84
 
Try this site: http://www.jbmballistics.com/
At the top hit: calculations
Then hit: trajectory simplified
 
TheSnake said:
It is a good site but I need to know what minimum MOA adjustment the scope needs to be given a 20MOA base.


If you have a scope that has 35 moa of adjustment and plan to shoot longer range get a different scope.

Next this is how you would figure what base to get. If the scope has 50 moa of adjustment then 25 up and 25 down. Considering it usually take between 5 and 10 moa to get back to zero with how high your scope is off the center of the bore. You would be hard pressed to get their with a 20 moa base and the 25 minutes of down but it might work. We use the 5.5-22 night forces all the time and with med or high rings we usually have around 5-10 moa left going down when the scope has 105 minutes and a 40 moad base. Usually giving us almost at or real close to 100 minutes of up left in the scope off a 100 yard zero. You need to figure on a base that has a few more minutes then the scope has going down.

To make it more clear when i say up/down i mean point of impact.
 
TheSnake said:
So to further question this topic, I am shooting a 6.5X47L at what I think will be about 2850 FPS with 130 GR Berger VLD. I have a 20MOA base already. What MOA adjustment range will my scope need to be for me to be able to zero in at 200 yards but still be able to dial out to 1000 yards? If a scope is listed with a 35MOA adjustment range, does that mean it is 17.5 up and 17.5 down or is that not necessarily the case? Below are my drop estimates. Thanks for the help.

Range Velocity Trajectory
(yards) (fps) (MOA)
0 2850 0.00
100 2684 1.59
200 2523 0.00
300 2368 -2.27
400 2219 -4.89
500 2075 -7.81
600 1937 -11.04
700 1805 -14.62
800 1680 -18.57
900 1562 -22.96
1000 1452 -27.84

You answered your own question. Your scope has 35MOA of adjustment. Get a set of Burris signature zee rings with the inserts, screw your scope all the way in and zero the scope with the inserts at 200 yards. Now you have the 35MOA of UP in your scope, no need for 20MOA bases.

A MOA is a MOA, it doesn't matter if it is talking about a scope, drop, drift whatever. If you only need 27MOA to get to 1000y and your scope has 35MOA of adjustment, there you go.
 
Thanks SpencerC. I guess I failed to mention that the 20MOA base is already glued to the action and I do not want to remove it. I was hoping to calculate this with that in mind. My thinking is that a 40MOA scope will do. I will need to crank it down about 18MOA or so to compensate for the base and be Zero at 200 yards. That should give me about 38MOA up when I am done. Does this sound correct or am I way off base?
 

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