Zero angle question
- Thread starter Mike240
- Start date
Calculated into what? The amount of moa in the base or mount doesn’t matter when zeroing anymore than how much you may need to adjust to zero.
Thats just an element I trying to clarify in the head in the “zero range vs zero angle” thing. If having 30 moa in scope mounting factors in or not. If not then cool. Just left thinking….have used Strelok Pro but want to check Hornady 4dof which asks for the choice to be made.
Base angle doesn't matter. Height of the scope above the bore and having an exact range of your zero target both do matter. If either one of those is off you could have troubles down the road.
Base angle doesn’t matter. That’s not the angle they are talking about when dealing with ballistics. It’s the angle to target.
Late to this party, but let me elaborate on what's been said (which is in essence, "just zero the scope and drive on, it's fine"). All I'm doing is explaining how the rail angle affects your scope's elevation "capability."
Your scope will have some amount of elevation range, measured in MOA or mils. In order to make the math easy, let's use MOA for this example.*
Let's say that your scope has 120 MOA total elevation range. This means that, when the reticle is centered, you have 60 MOA of "up" and 60 MOA of "down." If you have a flat rail, your centered scope's line of sight through the center dot or crosshair should be parallel to the bore.
If you mount your scope on, say, a 20 MOA rail, your centered reticle line of sight is pointing 20 MOA down, toward the axis of the bore. To make your line of sight through the center dot or crosshair parallel to the bore, you have to dial 20 minutes of "down" into your elevation, pushing the line of sight UP. The 20 MOA rail effectively adds 20 MOA of "up" to your scope's range and removes 20 MOA of "down" - so you have 80 MOA of "up" range from center and 40 MOA of "down."
That's it. The elevation angle of the rail affects only the scope's up/down range as described above. In terms of your ballistic solver, all you need to know is the linear distance between the center of the bore and the center of the scope tube at the turrets.
------------
* Most people here prefer (more appropriately, demand) mils reticles. There's nothing wrong with MOA and there are 9,873,452,121 threads about MOA vs mils and o gawd no I ain't goin' there... just do yourself a favor and get mils if you still have a choice. Then the 20 MOA rail in this example can be considered a "5.8 mils rail."
Your scope will have some amount of elevation range, measured in MOA or mils. In order to make the math easy, let's use MOA for this example.*
Let's say that your scope has 120 MOA total elevation range. This means that, when the reticle is centered, you have 60 MOA of "up" and 60 MOA of "down." If you have a flat rail, your centered scope's line of sight through the center dot or crosshair should be parallel to the bore.
If you mount your scope on, say, a 20 MOA rail, your centered reticle line of sight is pointing 20 MOA down, toward the axis of the bore. To make your line of sight through the center dot or crosshair parallel to the bore, you have to dial 20 minutes of "down" into your elevation, pushing the line of sight UP. The 20 MOA rail effectively adds 20 MOA of "up" to your scope's range and removes 20 MOA of "down" - so you have 80 MOA of "up" range from center and 40 MOA of "down."
That's it. The elevation angle of the rail affects only the scope's up/down range as described above. In terms of your ballistic solver, all you need to know is the linear distance between the center of the bore and the center of the scope tube at the turrets.
------------
* Most people here prefer (more appropriately, demand) mils reticles. There's nothing wrong with MOA and there are 9,873,452,121 threads about MOA vs mils and o gawd no I ain't goin' there... just do yourself a favor and get mils if you still have a choice. Then the 20 MOA rail in this example can be considered a "5.8 mils rail."
Zero angle is the angle between the scope axis and bore axis. How would the base angle not make a difference?
Angle of the rail does not matter. Putting on a 20 MOA rail does not change the "zero angle."
The Hornady 4DOF calls it zero angle but you could just call it initial conditions. When you zero the rifle, you input the actual measured distance to target, if you have it. Pretend for now that it is 100 yards. Input your barometric pressure, specifically station pressure. (Where I live is around 30.) Altitude above sea level. For example, The Colony, Texas is 554 to 591 feet ASL. Station pressure 30 inches.
edited to add: No, I don't live in The Colony. I drive through there twice a day during the week and shoot there, sometimes.
Input relative humidity, temperature, even wind, if you have it.
Input all of this in your rifle environment in your app. Then, when going to calculate a shot, input the distance and atmospherics of where you are taking the shot and the software will adjust. That way, you zero one time, anywhere and don't have to re-zero each time at a new destination.
This can be preferred over just the 100 yard zero because not all ranges are 100 yards on the dot and some atmospherics can influence the shot, especially cold bore.
At least, that is how I understand it. I could be wrong.
Why do they call it zero angle?
"Why do birds suddenly appear? They drop shit whenever you're near.
Just like me, they long to be close to you."
Botched lyrics from the Carpenters' song.
The Hornady 4DOF calls it zero angle but you could just call it initial conditions. When you zero the rifle, you input the actual measured distance to target, if you have it. Pretend for now that it is 100 yards. Input your barometric pressure, specifically station pressure. (Where I live is around 30.) Altitude above sea level. For example, The Colony, Texas is 554 to 591 feet ASL. Station pressure 30 inches.
edited to add: No, I don't live in The Colony. I drive through there twice a day during the week and shoot there, sometimes.
Input relative humidity, temperature, even wind, if you have it.
Input all of this in your rifle environment in your app. Then, when going to calculate a shot, input the distance and atmospherics of where you are taking the shot and the software will adjust. That way, you zero one time, anywhere and don't have to re-zero each time at a new destination.
This can be preferred over just the 100 yard zero because not all ranges are 100 yards on the dot and some atmospherics can influence the shot, especially cold bore.
At least, that is how I understand it. I could be wrong.
Why do they call it zero angle?
"Why do birds suddenly appear? They drop shit whenever you're near.
Just like me, they long to be close to you."
Botched lyrics from the Carpenters' song.
I'm not familiar with the Hornady app, but isn't that just the same as zero range but with the added benefit of environmental data at the time of zeroing? Or am I not understanding zero angle correctly?
I kind of understand it that way, too. Zero Angle is just perhaps a fancy word for saying initial conditions.
Because really, if you wanted to, you could zero at 50 or 75 yards. Whatever you like. Input that in you rifle environment and it should make calculations based on that. It's just that the 100 yard or 100 meter zero makes math easier.
Yup no idea how people zero there than hit targets. lol
There's no follow-on correction needed after having the app calculate zero angle regardless of base incline. Just so that's clear.
However, if you went from a rifle with a 0 MOA base zero angled, then put in a perfectly machined 30 MOA base, you could add 0.5 degrees to your zero angle and should impact where the App says ( 30 MOA high). However, you're still zeroed roughly 30" high at 100 so most sane people would slip the turrets and re-zero angle and it would end up likely very close to the original ZA.
Hopefully that's clear as mud.
However, if you went from a rifle with a 0 MOA base zero angled, then put in a perfectly machined 30 MOA base, you could add 0.5 degrees to your zero angle and should impact where the App says ( 30 MOA high). However, you're still zeroed roughly 30" high at 100 so most sane people would slip the turrets and re-zero angle and it would end up likely very close to the original ZA.
Hopefully that's clear as mud.
The Hornady guys actually mentioned this recently:
I'm thinking this 'zero angle' would essentially be the same as plugging in a zero offset, which also scales downrange in a similar manner.
I'm thinking this 'zero angle' would essentially be the same as plugging in a zero offset, which also scales downrange in a similar manner.
