I have never had a scope that was made to dial distance in the field, so I always sighted in at 200 yards and held high for the few shots I took at 300 plus yards. I bought a Vortex Viper 4x16x44 with dialable turrets to put on my 7mm-08. The factory ammo I'm using is Barnes Vor-tx 120 grains. The box and chart show a 200 yard zero which would be 1.6 inches high at 100, 7.1 inches high at 300, and 20.8 inches at 400. Under ideal conditions I would shoot 400 yards max. I want to zero at 100 and dial 3 and 400 yards. Again, I'm embarrassed!!! to ask, if I do that, do I take that 1.6 inches it would be high at 100, and add it to the 2,3-, and 400-yard drop, subtract it from the drops, or do the drops remain the same. I'm sorry my brain, somewhat dyslexic and 65 years old, just can't reconcile the thought.
Embarrassed to ask.
- Thread starter Duuane
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GSPHUNTER
WKR
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the only time to be embarrassed is when you are not sure and don't ask. Smart move. I had an instructor who told us, the only stupid question is the one you don't ask.
GSPHUNTER
WKR
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Nikon has a very similar one called, Nikon spot on.
This is my advice as well.
You can't simply add 1.6" to each distance, as it scales with distance. Assuming your Viper is an MOA scope, you will be zeroed at 100, then around 3.2" (which corresponds to 1.6 MOA) of correction on the dial) at 200.
Scope correction is done by angular measurement, not linear.
If you're figuring on a maximum of 400 yards, you can use the 1" per hundred yards rule of thumb. At, for example, 300 yards, 12" of drop would be 4 MOA on the dial. 7.5" of drop would be 2.5 MOA.
The flip side of that is that 2 MOA as an example is approximately 2" at 100 yards, 5" at 250 yards, or 8" at 400 yards.
Shooting beyond 400, I would work hard to understand the angular measurement and try not to think in terms of inches at whatever distance. It's a benefit at any range, but especially beyond that medium 350-450 range.
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First. Your box velocity is incorrect. It’s a “ballpark” for a certain barrel length in the chambering. It’s almost always quite a ways off from real world hunting rifles.
Second. Once you know your actual velocity, shooting using a chronograph, that is your starting number for a simple calculation.
Third. Sight your rifle in at 100 yards. Get a good true 100 zero with multiple “groups” that’s repeatable on multiple targets.
Fourth. Take your actual velocity and plug that number, plus some other basic bullet information numbers, into a specialized calculator. There are a million different options out there. I’ll tend to favor an App called StrelokPro. The detailed bullet information can be found on the manufacturers website.
Fifth. Measure from the center of your scope (reticle) to the center of the barrel. You will need this accurately measured to plug in a proper “sight height” into the calculation.
Sixth. Stop thinking in inches when dialing. Just use MIL or MOA (whatever your scope uses) and turn the elevation turret according to the calculated numbers. This will likely get you very close or will more than likely get you “hits” on an 8” target at the yardages you mentioned. Shoot some groups at various/desired yardages and take note of the the number on the elevation turret for building a “dope chart”.
Message here with more questions.
Second. Once you know your actual velocity, shooting using a chronograph, that is your starting number for a simple calculation.
Third. Sight your rifle in at 100 yards. Get a good true 100 zero with multiple “groups” that’s repeatable on multiple targets.
Fourth. Take your actual velocity and plug that number, plus some other basic bullet information numbers, into a specialized calculator. There are a million different options out there. I’ll tend to favor an App called StrelokPro. The detailed bullet information can be found on the manufacturers website.
Fifth. Measure from the center of your scope (reticle) to the center of the barrel. You will need this accurately measured to plug in a proper “sight height” into the calculation.
Sixth. Stop thinking in inches when dialing. Just use MIL or MOA (whatever your scope uses) and turn the elevation turret according to the calculated numbers. This will likely get you very close or will more than likely get you “hits” on an 8” target at the yardages you mentioned. Shoot some groups at various/desired yardages and take note of the the number on the elevation turret for building a “dope chart”.
Message here with more questions.
Bolding for emphasis.
I didnt read the other responses.
Zero at 275 or so. You’ll be about 4.5 inch high at 150/175 and -6 at 350, -16 at 400.
Dial for further distances. You introduced an additional thought process to wade thru for a “chip shot” inside 400 yds.
I’ve read about guys losing 200-250 yd shot cause they were messing w they scopes. They shoulda just shot critter but instead have some “I was dicking w my scope over an inch or so and lost an opportunity” story. (Very dumb-dumb-dumb)
Forgive me, i been out west 2x diy and had 3006 w 150 gr at 2900 fps set to shoot out to 400 yards with a non-dialing scope. Shot muley at 220, antelopes at 25 and 350 yards. Never changed VX-2 scope or scope settings. I’m old school and decided to do the dead hold technique. Held on hair all 3 times so far.
Good luck to you. Whatever you do, commit to it and know it in case you gotta think on the fly. Neither way is better, just what you know by heart and do without thought.
Zero at 275 or so. You’ll be about 4.5 inch high at 150/175 and -6 at 350, -16 at 400.
Dial for further distances. You introduced an additional thought process to wade thru for a “chip shot” inside 400 yds.
I’ve read about guys losing 200-250 yd shot cause they were messing w they scopes. They shoulda just shot critter but instead have some “I was dicking w my scope over an inch or so and lost an opportunity” story. (Very dumb-dumb-dumb)
Forgive me, i been out west 2x diy and had 3006 w 150 gr at 2900 fps set to shoot out to 400 yards with a non-dialing scope. Shot muley at 220, antelopes at 25 and 350 yards. Never changed VX-2 scope or scope settings. I’m old school and decided to do the dead hold technique. Held on hair all 3 times so far.
Good luck to you. Whatever you do, commit to it and know it in case you gotta think on the fly. Neither way is better, just what you know by heart and do without thought.
- Thread Starter
- #10
Thanks for the replies. I don't have a chronograph but I'm sure one of my friends does, I've never asked them. Obviously, I'd prefer a shot at close range, but if the only shot I get on a muley is a longer one, I don't want to take any chances with bullet drop, and if I don't time to get it right, I have no business taking the shot. The longest distance I've killed an animal was 335 yards on a Newfoundland moose with a 300 win mag zeroed at 200, and I held high for the distance based on the data on the ammo box. I had plenty of time and a rock solid hold.
As said earlier the listed velocity is likely just close.
Zero at 100. Set turret to zero here. Now you can add from here as many clicks (.25moa or .1mil depending on your model) as it takes to get zeroed at your chosen distance.
If you want to shoot exactly like you have up until the turret scope showed up in your life, come up to 1.75 (or whatever you like to strike high at 100) moa....and you're back to your old ways.
Zero at 100. Set turret to zero here. Now you can add from here as many clicks (.25moa or .1mil depending on your model) as it takes to get zeroed at your chosen distance.
If you want to shoot exactly like you have up until the turret scope showed up in your life, come up to 1.75 (or whatever you like to strike high at 100) moa....and you're back to your old ways.
You don't "need" a chronograph to predict the velocity AS LONG AS you can physically validate your corrections in the field.
Example....box velocity predictions are used and you're instructed to hold 4moa at 300yds and 5.75 at 400. You shoot and find those impact low by 1.5" at 300. Then you'll add the 2 extra clicks to your known data vs prediction and record that. If 400 strikes 2" low.....correct it by addind two more clicks....record and repeat.
This becomes your real world data for these distances....not guesses.
Validation by chronograph adds another necessary step in which you should validate the scope itself doing a tall target test.
Example....box velocity predictions are used and you're instructed to hold 4moa at 300yds and 5.75 at 400. You shoot and find those impact low by 1.5" at 300. Then you'll add the 2 extra clicks to your known data vs prediction and record that. If 400 strikes 2" low.....correct it by addind two more clicks....record and repeat.
This becomes your real world data for these distances....not guesses.
Validation by chronograph adds another necessary step in which you should validate the scope itself doing a tall target test.
@Duuane , this thread has explicit instructions for you. Exactly the same for moa if thats what you got.
rokslide.com
How to use a mil/mil scope-reticle, turrets and proper usage
I have gotten a bunch of requests to write up a "how to" for using mil reticle scoots. In this case the SWFA Milquad reticle. It is the 6x42mm SS with MQ reticle in the pictures, however the process and use is the same as long as you have a scope who's reticle matches the turret adjustments-...
rokslide.com
- Thread Starter
- #14
Mike D Texas
WKR
You owe it to yourself and the game you are hunting to verify and be confident that you can hit at the distances you are planning to shoot. If money is your biggest concern, keep your distances short.
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cacklercrazy
WKR
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- Apr 15, 2014
- Messages
- 379
How do you check the dialing?
I make my own tall target from a sheet of cardboard. Bring it to the range, level it out, shoot to verify.
- Thread Starter
- #18
Texas Mike, you're 100% right I owe it to the animal to get it right. Money isn't a factor in how many shots I will take to get it right, I just remember when rifle ammo was about half the price it is now. Good times, good times! The range down the road goes to 300 yards, the range at my house is 150, but I can safely make 400 yards happen, which I will do.
It might have something to do w our ages.4.5" high at 150yrds LOLnotta friggen chance.
I can see sighting in at 100. And then adjusting it up a bit, if you are goona plop down on a landing or something.
But no way would I have anything zeroed that far out
Many guys dont know the trajectory of their bullets and are amazed to know that a bullet’s rise and fall can be covered by their handprint out to 300 yards. Go figure.
Don’t make it any more complicated than it is.
Agree with Rob5589 manufacturers data is just a parameter. You will figure out actual drop at the range But that's the fun part.
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