Scope Levels- Why?

[milo-2]

I thought about it for a second What happens when I dial up 20moa?

If the reticle is still level, you have dialed up 20 moa and should hit, all else considered. Let's put this on the table, I try level the whole platform myself, but I just mounted a scope 2 weeks ago and trusted a raceway level, slightly off, I have not missed beat, I level the reticle.

 

[PNWdude67]

I have read a lot of threads on this forum. Guys will swear that cleaning primer pockets makes for a more consistent shooter because of that attention to detail. Now I see guys claiming they can "eyeball" level without issue in the field or "train" themselves to hold level. I don't worry 'bout clean primer pockets and find it has no effect on load consistency. We DO have levels referencing the reticle being plumb, and use them every shot even under PRS/NRL time constraint. Especially, in the team matches where we are referencing POI off each other. I have not seen any top shooter without a level mounted in the matches we attend. We all rely on the level to mitigate the POI shift that occurs at any distance if the rifle is not held consistently from shot to shot or position to position. The one constant value we have when calculating our shooting solution is gravity and how it will effect our specific projectile. Assuring our sighting device is plumb as we break the shot allows us to take advantage of that factor as we dial or hold over and hold left or right for wind. It gives us a sound reference point. Shoot with both eyes open and position your level in such a place it's in line of sight and you will see it without breaking your sight picture. Train yourself to use it as part of your routine. This can be done quickly and yes we do it in "PRS" matches under time constraints. I chose to compete in rifle matches for two reasons, one it's super fun and two to become a better shooter in the field while hunting at longer ranges. The bubble levels from Vortex or MK machine and others work well, that said I recently started using the digital "send it level" and like it.

 

[RD57]

All my rifles that I shoot beyond 500 yards has a level ... for all the reasons already posted. For shooting at targets with rifles that do not have a level, I take a small level down range when I put my target up and ensure that it is plump with gravity ... now all I have to do is properly align my reticle on the target and squeeze off some good shots.

 

[tony d willIiams]

I am a bit nerdish and believe that any job deserves being done properly. My opinion and I'll stand by it.

I placed my rifle strapped down on a sled that was strapped down a on a weighted table that was tied to the ground. Line bore picture through barrel to target, set on level plain, and scope similar just for a reference starting point.
I used my machinist level, dev lines = 0.0001 of inch, to level the rifle. I used the same level on the scope.
Then I zeroed at 100 yards, stepped it out to 400 yards and set my bottom vertical CRS at 400 yards.

I do not use a level on my scope. I line on target, and when my vertical reticle is drifting centered up and down on POA I will slow and stop my breathing before squeeze. The rifle/scope is level with earth.
At short distance the lack of level is negligible as a miss by an inch is still deadly, but why take a chance? A quick death prevents pain on the animal's part and tracking, guilt on my part.

If you notice that the POI is drifting farther and farther to one side which becomes more severe as the distance becomes greater and greater, it might be a good time to head out and re-level your rifle/scope.

edit; I forgot one thing, sorry. I will hang a plumb bob at distance on a wind free day. I will set my rifle so the vertical retical is lined properly with the yellow string on plumb bob. I will then look thru barrel and ensure the yellow cord is through vertical centreline of barrel, best as my eye can tell. Yes, I overdo things, but I have fun doing it.

 

[barefoot1]

It's obvious which poster has tried using a level and which ones have not.

The average person can not resolve an angle any better than plus or minus 3 degrees with their eyes.

Rifle cant (what you create when your reticle isn't properly aligned with the vertical and horizontal of the stock) causes the bullet to move to one side and down from where your muzzle is pointed...no, your barrel doesn't care how the reticle is aligned but the stock does and when the stock and the scope are out of alignment your impacts become more random. At short range it's a fairly small error that most shooters can't see (unless you are a bench rest shooter), but at long range it becomes very obvious.

https://www.shootingillustrated.com/articles/2016/3/28/rifle-scope-reticle-cant/


View attachment 190971

From the cant error information in the above picture, you can see that most shooters aren't going to believe that a level is useful because they don't shoot accurately enough to even see the error. A 1 inch error at 200 yards is usually written off as "...just how I shoot" and it isn't even recognized as a mechanical problem that can be fixed. When you start trying to hit accurately (1 MOA or better) at ranges past 600 yards you'll see the problem pretty quickly. Go shoot at 1000 yards and when you can't hold a group that's better than 3 or 4 MOA (30 or 40 inches) you'll start looking at that cant angle.

Due to the height of the scope above the bore, any cant will create and arc with the bullet impacts on the target. Most of the error will be horizontal but at longer range the vertical will become large enough to cause problems.

Aligning your reticle to a poor shooting position causes the muzzle to move up and down in one plane and the scope to move up and down in another. The longer the distance the more difference there will be between those two planes. Ever wonder why you had to add windage to your scope as you increased the range when there wasn't any wind? Well now you know why (your scope could also have a problem but that's another issue with reticle alignment), as the range increases you have to add more and more windage with every elevation change because of the difference between how the stock/muzzle is moving compared to how the reticle moves.

That is a great explanation. Thank you sir!

 

[Canadian Bushman]

Its easy to think you are holding your stuff level and true when you dont have anything to show you that you arent. So if you dont have a level and are claiming you dont need one. How do you know?

Most people are pretty good at aligning their reticle to something in their view that is level or close to it.

The real test is mid to long range shots at at target or animal that is crooked against a background that is crooked from a shooting position that is crooked. When all your typical references are gone, you could be of 10-15 degrees pretty easily.

Many of times ive gotten set up on a target and looked up at my level and was way off.

Anyways, they are cheap. My aci levels cost less than $30 and are very fickle.

 

[Mram10us]

I am not certain how much he cants his rifle stock, but I know his his scope reticle is plumb (repeatably so due to his bubble level). I am certain that our mutual friend has a pronounced cant to his stock and he rings steel out to 1300 yards all the time. It is not a theory. I know exactly where/how my thinking went wrong when I used to think the bore and optical axis needed to be plumb. One day I may record a trip out on the range, but for now - I have a comfortable system that I know works. In the meantime, I am merely trying to help others as my brother tried to help me. Based on your signature, I am just trying to pass on wisdom!

Say what you want but if your reticle is not level with gravity AND level with the bores vertical plane, you will shoot left or right. You can blame wind or spin drift, but you will be off and low. Think of it from a geometric or trigonometric lens. Don't listen to me. Listen to JE Custom. He knows what he's talking about. Please do video. This isn't a p...... contest. It is an attempt to steer the OP straight and avoid misinformation

 

[Mram10us]

If the reticle is still level, you have dialed up 20 moa and should hit, all else considered. Let's put this on the table, I try level the whole platform myself, but I just mounted a scope 2 weeks ago and trusted a raceway level, slightly off, I have not missed beat, I level the reticle.

So you leveled the action with the scope? Great. Have you done a ttt to verify? Levels definitely get you close, no argument. Point to the thread is we cannot verify what level is in the field without a reference (anti cant) and we can't shoot straight without verifying the rifle and scope are aligned. Off to cook steaks . All yours JE!

 

[MarshMello]

Sorry if it's been said already. Too many replies to sift through. For long range shooting, cant is extremely important. My chassis has a built in bubble level. My hunting rifles I level the gun with 2, sometime small 3 bubble levels off the action and/or rail and split the difference (it's usually minor and I know it's not perfect, just trying to minimize margin of error). I hang a rope with a weight at 100 yards (my plumb bob) and align the verticle reticle with that and tighten her down, keeping the gun level. Works for me and my guns have tracked true to 1200.

 

[tony d willIiams]

Your words and JE Custom are correct. Geometrically and by the laws of physics if all is not level and plumb, the rifle will only be accurate at the dial-in distance.

I rushed once and I was overjoyed as the gnats were being damaged, until I doubled the distance from dial-in. I put it away until I had the time to set it up properly.

 

[Mc Fraser]

My biggest challenge when mounting a scope is finding the true horizontal zero of my rifle. What others are doing and how do you know its true horizontal?

 

[An Idahoan]

Say what you want but if your reticle is not level with gravity AND level with the bores vertical plane, you will shoot left or right. You can blame wind or spin drift, but you will be off and low. Think of it from a geometric or trigonometric lens. Don't listen to me. Listen to JE Custom. He knows what he's talking about. Please do video. This isn't a p...... contest. It is an attempt to steer the OP straight and avoid misinformation

I have thought about this for quite some time. I wish, as another poster said, that it only took me a few seconds to figure it out. I am not quite that brilliant. But alas, if you zero properly, and your reticle is plumb, you'll be good at all ranges. This is not personal, nor is it a match of any kind. Brilliant people are wrong on occasion. I am trying to steer the OP and anyone else is his situation straight as well. For the record, I agree with you in that the reticle MUST be plumb or else you'll be off left/right and low. The rest of it, not so much.

 

[Mram10us]

I have thought about this for quite some time. I wish, as another poster said, that it only took me a few seconds to figure it out. I am not quite that brilliant. But alas, if you zero properly, and your reticle is plumb, you'll be good at all ranges. This is not personal, nor is it a match of any kind. Brilliant people are wrong on occasion. I am trying to steer the OP and anyone else is his situation straight as well. For the record, I agree with you in that the reticle MUST be plumb or else you'll be off left/right and low. The rest of it, not so much.

I would encourage people to try the tall target test. It verifies our scope mounting, regardless of how we choose to do it. I enjoy the debates we all have because we all get better.

 

[jimbires]

good discussion Fellas . I'm a tall target guy too , it's not hard so why not . I admit I've never tried to shoot with a true reticle , and cant in the rifle . this is one more thing I've always felt " junk in , junk out "