Rifle Scopes Where to set zero on a 20moa base???

Grand Poo Bah

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Minuteman
Aug 1, 2011
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0
53
Eugene, OR
I need some help figuring this out. I have a Savage 12 f/tr with a Horus Raptor 6x16 and an H-25 recital and a 20moa base. I'm just starting to load test this and need some advice on where to set the zero. Do I set it at the zero line or do I go up from that line? I have easy access to a 100 yard range, and have very limited access to a 200 yard range. Where on the recital do I set my zero so i have enough elevation to reach out to 1000.

I have no idea if this makes since or if you need more information about what I have. Thanks for your help
 
Re: Where to set zero on a 20moa base???

I never used a Horus but, I thought even on a Horus reticle that zero is center of the crosshairs. I remember an article a while back about the first generation of the reticle. It said that finding your zero is the same way as conventional methods, then you leave it at that, and use your holds. I could be wrong.
 
Re: Where to set zero on a 20moa base???

that is correct, I'm asking where on the recital to zero. I have vertical hash marks above the zero line. how do I adjust for the 20 moa base? If I zero at the zero line it doesnt make sense to have the elevated base. how do I make the adjustments when I go out to distance? I'm looking at 1000 yards
 
Re: Where to set zero on a 20moa base???

I don't understand. It shouldn't matter if you have a 20 MOA base or a 0 MOA base. Zero it in the center of the reticle either way. If this is wrong, I'd like to hear why so I can understand better.
 
Re: Where to set zero on a 20moa base???

Well the easy answer is the center crosshairs. Other than that if you have the manual for it it should say, and if you don't have the manual I bet their website does.
As for the 20 MOA base it doesn't make a difference as long as you are able to zero it. The angled base effectively let's you dail out farther. For example if you had a scope that could only dail out to 800yds with a flat base, the 20moa base would let that same scope dail out to 1,000yds or more. So with a horus it wouldn't matter since those are meant to be used without dialing.
 
Re: Where to set zero on a 20moa base???

zero the crosshair at 100 yards. you will have no trouble getting to 1000 with that base. 1000 should be near the 8 grid.
forget about the vertical hash marks.
 
Re: Where to set zero on a 20moa base???

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Grand Poo Bah</div><div class="ubbcode-body">that is correct, I'm asking where on the recital to zero. I have vertical hash marks above the zero line. how do I adjust for the 20 moa base? If I zero at the zero line it doesnt make sense to have the elevated base. how do I make the adjustments when I go out to distance? I'm looking at 1000 yards </div></div>

You don't understand the purpose of a canted base. You still zero the scope by putting the center crosshairs on the point of impact. That's what you do whether you have a zero MOA base, 20 MOA or 30 MOA.

What the cant does by angling the scope down is give you 20 MOA of extra upward adjustment when you dial out to longer ranges.

For example, let's say you have a zero cant base and a scope with 50 MOA adjustment that zeros at mechanical zero (25 MOA from the bottom) at 100 yards. You only have 25 MOA of upward adjustment.

If you use a scope base with a 20 MOA cant instead, your 100-yard zero will be 5 MOA from the bottom so you'll have 45 MOA of upward adjustment.
 
Re: Where to set zero on a 20moa base???

What caliber are you shooting? Look at a drop chart for your particular round and see if the H25 reticle provides enough marking to get to 1000 with a 100yd zero. My guess is it does.

If so, zero at 100 using the center crosshair.
 
Re: Where to set zero on a 20moa base???

Poo Bah,
Your scope almost certainly came from the factory with the reticle centered in the middle of the elevation travel (ie. optically centered). Same thing for windage. If you mount it on a 20 MOA base, that means it's <span style="font-style: italic">pointing down</span> (toward the barrel) at an angle of 20 MOA. That means you have to raise the scope/rifle up by 20 MOA in order to bring the reticle on target. However, that means the barrel is <span style="font-style: italic">pointing up</span> by the same amount with respect to the line of sight through the scope. End result is that your POI will be in the neighborhood of ~19 MOA high at 100 yd with a 20 MOA base and the elevation turret at the factory zero setting. To get it close, you will need to dial down around 19 MOA (~5.5 mil). Dialing down from the factory zero (middle point of the reticle elevation travel) to establish a zero at some range such as 100 yd is how a canted base gives back some of your elevation travel. To see a good example of this, leave it set on the factory elevation zero and fire into the dirt of a berm at 100 yd. The dirt impact is easy to see and should be about 19" high with respect to your POA at that distance.
 
Re: Where to set zero on a 20moa base???

To Zero a scope, put a target at 50 yards (or 100 if you dont have a 50 yard range), the bigger the better, but 2'x2' or so is usually good enough.

Put your rifle on a good rest. One where you can adjust the scope without the rifle moving. It doesnt have to be an expensive rest a $50 maintenance cradle or bags will work.

Take the bolt out of the rifle and look down the rifle barrel and adjust the rest so the barrel is pointing at the center of your target.

Adjust the scope so the scope cross hairs also point at the center of the target. (The major crosshairs that go all the way to the edge of the scope)

Shoot 3 shots. You should be on the paper. If you aren't you need to get a bigger target, move the target closer or have a friend look and tell you where the bullet is hitting the backstop.

Once you are target, fine adjust the scope from there.
 
Re: Where to set zero on a 20moa base???

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: dreiaugen</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Grand Poo Bah</div><div class="ubbcode-body">that is correct, I'm asking where on the recital to zero. I have vertical hash marks above the zero line. how do I adjust for the 20 moa base? If I zero at the zero line it doesnt make sense to have the elevated base. how do I make the adjustments when I go out to distance? I'm looking at 1000 yards </div></div>

You don't understand the purpose of a canted base. You still zero the scope by putting the center crosshairs on the point of impact. That's what you do whether you have a zero MOA base, 20 MOA or 30 MOA.

What the cant does by angling the scope down is give you 20 MOA of extra upward adjustment when you dial out to longer ranges.

For example, let's say you have a zero cant base and a scope with 50 MOA adjustment that zeros at mechanical zero (25 MOA from the bottom) at 100 yards. You only have 25 MOA of upward adjustment.

If you use a scope base with a 20 MOA cant instead, your 100-yard zero will be 5 MOA from the bottom so you'll have 45 MOA of upward adjustment. </div></div>

What he said, zero at 100 at center reticle
 
Re: Where to set zero on a 20moa base???

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Chiller</div><div class="ubbcode-body">100 yards seems to be the standard for a zero range</div></div>

it is.. but i use a 200y zero
 
Re: Where to set zero on a 20moa base???

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Grand Poo Bah</div><div class="ubbcode-body">I need some help figuring this out. with a Horus Raptor 6x16 and an H-25 recital Where on the recital do I set my zero so i have enough elevation to reach out to 1000.
</div></div>

The Horus H25 reticle is calibrated with over 40 Mils of vertical markings. Only about the first 15 mils are visible in the field of view when set at 16x magnification. The H24 has -4 mils of markings above the 0 marking. The rest of the reticle is visible as you reduce the magnification. This is the 16x view:

H25_Huge-600x600.jpg


You didn't state the bullet, muzzle velocity, or air density where you shoot but you'll proably be ok.

The scope should be adjusted so the zero distance of your ballistic software and the zero target distance will fall on the 0 Mil line of the reticle. This Raptor scope doesn't need or expect a 20 moa tapered base, but since the scope knobs have 56 MOA of range you should be able use the scope with the 20 MOA base under it and still have ((56/2)-20)= 3 MOA of adjustment. Personally I'd use a flat base with the H25 reticle.

When you set up the scope pick the zero range you want. It must be the same as you use for your ballistic software or range card. Other than that there's nothing special about 100 yards. Don't put the zero distance further than 4 mils of drop lower than the highest point of the trajectory or you'll run off the top of the reticle at some distances.

You'll have plenty of reticle to reach 1000 yards unless you're shooting subsonics, though you may have to turn the magnification down some to see the point of impact for low velocity cartridges.

15 mils at 1000 yards is 15 yards and 51 MOA.
40 mils at 1000 yards is 40 yards and 137 MOA.
The fact the scope only has 56 MOA of vertical adjustment is not important. Remember that the concept of the Horus reticle is that you don't need to change the windage or elevation knobs except to zero the rifle.

 
Re: Where to set zero on a 20moa base???

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Grand Poo Bah</div><div class="ubbcode-body">I need some help figuring this out. I have a Savage 12 f/tr with a Horus Raptor 6x16 and an H-25 recital and a 20moa base. I'm just starting to load test this and need some advice on where to set the zero. Do I set it at the zero line or do I go up from that line? I have easy access to a 100 yard range, and have very limited access to a 200 yard range. Where on the recital do I set my zero so i have enough elevation to reach out to 1000.

I have no idea if this makes since or if you need more information about what I have. Thanks for your help </div></div>


Set your POI to be dead center of the crosshairs at 100 yards both for elevation and windage. DOCUMENT your load and the conditions, baro, temp wind etc. Then as your range increases you simple use your DOPE to hold for elevation and windage no need to dial at all.

If and when you move to a different location or the conditions change from your baseline condition use your DOPE for whatever your current DA is as needed to dial a change in scope zero to keep your POI the same as wherever you zeroed the rifle/scope/load in the first place. Easy as pie.

HTH!