Best way to level a scope

[7Green]

Imo, levels on the turret are close, but not absolute. A plumb bob or straight line drawn level is far better because you actually align the crosshairs level. I have seen some scopes off by a percentage when using the turret. You can always use the same vertically true line to test your tracking on the scope. Each round should follow the line up. Assuming you have a solid hold and rest, if it shoots to the left or right of the line as you adjust the scope, then your scope isn't true. As always, remember to level the gun first before mounting the scope.

 

[Scotchmo]

… if it shoots to the left or right of the line as you adjust the scope, then your scope isn't true. As always, remember to level the gun first before mounting the scope.

Assuming that you have not changed target distance, that test is a good indication that the turrets don’t track with the reticle (defective scope). It does not tell you if the scope is mounted correctly.

 

[stanginthe11s]

the only thing that needs to be leveled is the scope and you should do it from the turret/knobs because that is what moves the POI. you want your adjustments to be true to the direction. if your reticle doesn't match your turrets either send it back or set it to the way to shoot. each way will solve a problem while giving you a different problem.

 

[PBuffa]

Most scope mounting strategies that involve the use of levels or wedges are making a variety of assumptions about the perfectness of critical features of the gun, scope, and mounts. Granted, frequently these items are close enough that you’ll get a better result than by just eyeballing it, but it’s frustrating to see expensive “professional” jigs that will leave you with an improperly aligned scope if something isn’t perfect. For example, it’s not uncommon for the reticle to be rotated a couple of degrees relative to the turret caps, or for 3/8mm or 11mm rings to be offset slightly, or a variety of other issues.

What matters is that the reticle is aligned to the bore. The good news is it can be done with no special tools. All you need is a mirror.

But first let's establish that the requirements to eliminate cant error are:

1. Align the scope's reticle with the rifle's barrel.
2. Hold the reticle level when shooting.

Item 1 deals with scope cant…i.e. mounting the scope incorrectly.

Item 2 deals with gun cant…i.e. holding the gun incorrectly.

To correctly align the scope to the barrel, set up a mirror at a distance of, say, 5 yards and set your AO to 10 yards. Look through the scope at your reflection in the mirror. Twist the scope in the mounts until the vertical bar of the reticle simultaneously bisects both the muzzle and objective bell. Then lock it down. At this point you have eliminated scope cant (item 1). If it's hard to see your muzzle, add a little dot of White Out or take a dot from a hole punch and tape it to the muzzle with clear tape.

Now to eliminate rifle cant, install and use a level. View a known good plumb line (e.g. hanging string) through the scope and orient the rifle so it precisely aligns to it. Now affix your level so it shows level. From now on when you're shooting, hold the rifle so it shows level and you can be sure you've eliminated both potential sources of cant error.

By the way, don't buy a level that attaches to the scope rail. There is no guarantee it will show level. Instead, get one that attaches to the scope tube so you can rotate it and lock it down where it shows the proper level.

Outstanding. I need to do this on both of my pcp’s as one is new and I just installed a Maddog stock on the other. I have always fought rifle and scope level. Thank you!

 

[7Green]

Assuming that you have not changed target distance, that test is a good indication that the turrets don’t track with the reticle (defective scope). It does not tell you if the scope is mounted correctly.

I disagree, I would argue it does if you leveled the gun and and aligned the crosshairs when 1st mounted. You would obviously need a permanently afixed level mounted to the scope or base mount of the gun so you always held the gun true.

However, when aiming at a true vertically level line your crosshairs should align perfectly with that line. Heck, you could even make a vertical and horizontal line as an aiming point down low. If your gun is level, your scopes crosshairs should fall into true and match the lines drawn.

You are correct in that you can check tracking be it mil or moa if you set a target at a certain distance and mark where your round should place as you adjust the scope. They probably even have targets to print or purchase online for that.

I'm simply stating once the gun is leveled and the scopes crosshairs aligned with a true vertical line like a plumb bob, a level straight edge or line drawn, you can track you round up and down on vertically drawn leveled line.

I think you may be misunderstanding what I mean.

 

[7Green]

Continuing. Distance doesn't matter with this test as we are not doing a true accuracy test for the tracking of the scope. We are simply making sure the round goes up the line as you adjust the scope and does not vere left or right of the line as you adjust the scope.

Say you are zeroed for 100 yards on a powder burner. You draw a true level vertical line on a piece of cardboard 50 yards away. Draw a small level horizontal line as a simple aim point near the bottom. Now shoot and hit close. Will be slightly off due to scope mounting height in relation to the bore and sight in distance, no biggie. Next, adjust up 10 moa/or mil, aim and shoot. Your round should track up the trued line. Adjust another 10moa/or mil. Same thing. Continue until your heart is content with your mounting.

Just a simple test to make sure your bullet tracks a true up and down with the scope. Not an official tracking test.

 

[7Green]

the only thing that needs to be leveled is the scope and you should do it from the turret/knobs because that is what moves the POI. you want your adjustments to be true to the direction. if your reticle doesn't match your turrets either send it back or set it to the way to shoot. each way will solve a problem while giving you a different problem.

I also disagree with this due to various manufacturing tolerances. Imo, The truest machined point in the scope is the glass etched reticle inside. That is what needs to be leveled and trued with the gun itself.

I do agree that if it is way off, send it back. However, I would be curious as to what certain manufactures tolerances are. I observed a Vortex pst gen 1 once that was off by at least a few degrees.

A separate consideration might be that while the internal of a scope may be machined true, the turret cap may not be. I don't know what various manufacturers tolerances are. Moa or mil tracking tests would show if the crosshairs track correctly.

Perhaps a another thread should be started with people checking the squareness of their turret caps.

 

[stanginthe11s]

all the ways mentioned achieve the same goal and all the ways will have their own issues, so really there is no right or wrong way. as long as you hit where you aim, you're as good as the next guy. you can go crazy trying to get everything perfect and I'm not saying there's anything wrong with that but realize at the end of the day, that bullet/pellet will want to do its own thing anyway and no, nothing flies straight in relation to the earth. consistency is key, so no matter how the gun is setup for you just be consistent.
all that being said, I have used all the techniques mentioned except Trigs, and all yielded the same results. I also have a rifle that if you looked at the reticle with the gun level you would say its way off, but the way the gun fits me when it's shouldered the scope is level. it is pointless to level that gun and fight or try to remember how to hold it every time. I prefer to know that in the moment, every time I shoulder that rifle, I will be on target without thought.
also, I like Trigs way because I haven't heard that one yet lol. but even that way can induce problems under the right circumstances.

 

[Scotchmo]

I disagree, I would argue it does if you leveled the gun and and aligned the crosshairs when 1st mounted. You would obviously need a permanently afixed level mounted to the scope or base mount of the gun so you always held the gun true.

However, when aiming at a true vertically level line your crosshairs should align perfectly with that line. Heck, you could even make a vertical and horizontal line as an aiming point down low. If your gun is level, your scopes crosshairs should fall into true and match the lines drawn.

You are correct in that you can check tracking be it mil or moa if you set a target at a certain distance and mark where your round should place as you adjust the scope. They probably even have targets to print or purchase online for that.

I'm simply stating once the gun is leveled and the scopes crosshairs aligned with a true vertical line like a plumb bob, a level straight edge or line drawn, you can track you round up and down on vertically drawn leveled line.

I think you may be misunderstanding what I mean.

Reading through your posts, I think you understand the problem fairly well. But something more to consider:

Your method will tell you if there is a problem, but there is no way to tell from that whether it is a scope mounting problem, or a built in turret tracking problem.

Likewise, lacking any measurable error with your method does not mean that the scope is mounted correctly.

+/- 2° is within the manufacturing tolerances of most turret vs reticle tracking. So, if there is no horizontal deviation in your single distance test method, you still might have a problem. Since you are only checking at one distance, it’s possible that a 2° tracking error completely counteracts a 2° mounting error. Even though it appears to track correctly at the test distance, if you move to a different distance and use holdover you will be off center.

Most scopes that leave the factory are probably within 1° and that’s mostly acceptable to me for a scope that will see clicking and holdover use. If one uses mostly holdover, mount the scope with the reticle aligned to the bore. If one uses mostly clicking, mount the scope with the vertical tracking aligned to the bore.

On my Hunter Division FT (no clicking) gun, I really don’t know (or care all that much) how the turrets track.

If someone is going to be zeroed and shooting at one distance only (benchrest?) none of it really matters.

 

[7Green]

I think we are all on the same page, just different perspectives on how to go about it. It all depends on how anal one wants to be and what the gun is used for.

On my Impact. I have an ffp Athlon Cronus mounted. I use the etched reticle 99% of the time and don't dial. I am using it mainly for hunting coyotes and turkeys though, so I don't need as much perfection. On my Borden built 280ai, I have a sfp March scope. On that gun, I dial in, but I also shoot much further than my airgun. The second reason is because it is a sfp scope (wish it was ffp).

 

[acetan]

I've using the Wheeler setup.

 

[cavedweller]

Most scope mounting strategies that involve the use of levels or wedges are making a variety of assumptions about the perfectness of critical features of the gun, scope, and mounts. Granted, frequently these items are close enough that you’ll get a better result than by just eyeballing it, but it’s frustrating to see expensive “professional” jigs that will leave you with an improperly aligned scope if something isn’t perfect. For example, it’s not uncommon for the reticle to be rotated a couple of degrees relative to the turret caps, or for 3/8mm or 11mm rings to be offset slightly, or a variety of other issues.

What matters is that the reticle is aligned to the bore. The good news is it can be done with no special tools. All you need is a mirror.

But first let's establish that the requirements to eliminate cant error are:

1. Align the scope's reticle with the rifle's barrel.
2. Hold the reticle level when shooting.

Item 1 deals with scope cant…i.e. mounting the scope incorrectly.

Item 2 deals with gun cant…i.e. holding the gun incorrectly.

To correctly align the scope to the barrel, set up a mirror at a distance of, say, 5 yards and set your AO to 10 yards. Look through the scope at your reflection in the mirror. Twist the scope in the mounts until the vertical bar of the reticle simultaneously bisects both the muzzle and objective bell. Then lock it down. At this point you have eliminated scope cant (item 1). If it's hard to see your muzzle, add a little dot of White Out or take a dot from a hole punch and tape it to the muzzle with clear tape.

Now to eliminate rifle cant, install and use a level. View a known good plumb line (e.g. hanging string) through the scope and orient the rifle so it precisely aligns to it. Now affix your level so it shows level. From now on when you're shooting, hold the rifle so it shows level and you can be sure you've eliminated both potential sources of cant error.

By the way, don't buy a level that attaches to the scope rail. There is no guarantee it will show level. Instead, get one that attaches to the scope tube so you can rotate it and lock it down where it shows the proper level.

@cavedweller

 

[2L8]

As @cavedweller says.
I agree.
Please read post #5
Simple, true, accurate and mathematics to back it up.
Try it.

Excellent topic!

Patrick

 

[Michael]

While there's lots of good info in this thread (and the links) there are a few aspects missing. These questions are regarding the mirror method.

First lets identify the goal. Is the goal to get the vertical crosshairs to split the Objective bell & the muzzle evenly? Or to get your windage crosshairs to intersect the muzzle evenly? Or both?

1. Should we start with the rifle on a rest and the action as level as possible?
2. Should we optically zero the scope prior to mounting?
3. Confirm that we should not adjust the turrets, only the position of the rifle facing the mirror (or the mirror itself) with shims.

Thanks

-Michael

 

[Bigragu]

While there's lots of good info in this thread (and the links) there are a few aspects missing. These questions are regarding the mirror method.

First lets identify the goal. Is the goal to get the vertical crosshairs to split the Objective bell & the muzzle evenly? Or to get your windage crosshairs to intersect the muzzle evenly? Or both?

1. Should we start with the rifle on a rest and the action as level as possible?
2. Should we optically zero the scope prior to mounting?
3. Confirm that we should not adjust the turrets, only the position of the rifle facing the mirror (or the mirror itself) with shims.

Thanks

-Michael

The few times I’ve tried I’ve struggled with the mirror method, especially when using a FFP scope as the X hairs are too thick. Then, the one time I thought I got it right, I put the gun away and later on when I mounted it on my tripod, it was then that I noticed the top turret was at a slight angle in relation to the action/pic rails.

I went back to using levels, a method that’s always worked for me

 

[Scotty1]

Like Augie, I found The mirror method frustrating and have gone to simply leveling the gun/pic rail, and then setting my vertical crosshair to a plumb line hung down range.

 

[Michael]

Like Augie, I found The mirror method frustrating and have gone to simply leveling the gun/pic rail, and then setting my vertical crosshair to a plumb line hung down range.

I am very familiar with the traditional methods, each of which have their faults. But the perfectionist in me is looking for more answers regarding the mirror method.

 

[Scotty1]

Roger that, I get that same compulsion and will likely try again myself.

 

[beerthief]

Lots of good info here. Reference # 5 for scope installing.

Parallax links & scope info:

1. How to Eliminate Parallax in a Riflescope (gunsandammo.com)
   
2. Parallax Adjustment for Scopes: Complete Beginner’s Guide (shootingmystery.com)
   
3. Parallax Adjustment – 2021 Guide on Understanding and Correcting Parallax - Gun Mann
   
4. RimfireCentral.com Forums - View Single Post - Derivation of Parallax Equation
   
5. The Scope, Sights, & Mounts Super-Sticky (questions? try here!) - RimfireCentral.com Forums
   
6. Rifle Scope Objective Lens Diameter Guide: Choose The Best Size (targettamers.com)
   [/LIST=1]
   
   

bookmarked all these site for later or repeat consumption .

 

[Smok3y]

While there's lots of good info in this thread (and the links) there are a few aspects missing. These questions are regarding the mirror method.

First lets identify the goal. Is the goal to get the vertical crosshairs to split the Objective bell & the muzzle evenly? Or to get your windage crosshairs to intersect the muzzle evenly? Or both?

1. Should we start with the rifle on a rest and the action as level as possible?
2. Should we optically zero the scope prior to mounting?
3. Confirm that we should not adjust the turrets, only the position of the rifle facing the mirror (or the mirror itself) with shims.

Thanks

-Michael

I will try to answer these based on my experience.

Is the goal to get the vertical crosshairs to split the Objective bell & the muzzle evenly? - This. The vertical cross hair will cover the scope and muzzle, so you are trying to get it to split them both down the center, proving that they are both aligned.

Or to get your windage crosshairs to intersect the muzzle evenly? Or both? - Not necessary. You are trying to make sure your scope and barrel are level with each other, so worrying with the horizontal axis is unnecessary unless you think it will help you more evenly see your vertical axis centering.
1. Should we start with the rifle on a rest and the action as level as possible? - I do try this to help keep everything stable during the process, but technically it shouldn’t matter. You should just see it angled in the mirror like you are angled in person. As long as you mount it with the vertical cross hairs splitting both evenly, when you level the rifle, they will both be level together. That being said, in a rest makes the whole process of setting up your scope and aligning it and tightening it down much easier when things are level and stable.
2. Should we optically zero the scope prior to mounting? - Not necessary.
3. Confirm that we should not adjust the turrets, only the position of the rifle facing the mirror (or the mirror itself) with shims. - I don’t think I have ever had to adjust my turrets, but maybe I have needed it to get the vertical line centered. The hardest part is getting the mirror set up and level, so that I can see my rifle across the room. My angles are usually all off and I have to keep adjusting it to find me at the desk. Once I do, it is just matter of getting it set up to a good view and then twisting the scope to get it right. I spend more time on the setup than I do leveling I think.