How to mount and level a rifle scope

There is no other activity in long range rifle shooting that can have more effect on your results than ensuring your scope is installed and set up correctly. This is like building the foundation for a new house. There will be many problems down the road if this is not done correctly.

The process is easy and can be done by anyone who has the ability to shoot a rifle. You just need to understand a few techniques and have the right tools to do it properly. Everything needed is pretty cheap. If you are a dedicated shooter, you might even already have everything you will need. Let’s get started.​

What do we want to accomplish?

Our objective here is to install our base, rings, and scope so that we have no movement now, or in the future of any of these components, and number two, to ensure that the set up is perfect for the shooter so he can perform at his best.

Being perfect for the shooter means there is no special effort made to see a clear, centered sight picture and the sight picture is stable. The shooter should be able to close his eyes, mount the rifle in the shooting position, and after opening his eyes should see the sight picture perfectly without having to crane his neck or shift his body in any way.

This is the primary reason you should never let the gun shop set up your scope. Most will set it up for the average shooter, not you specifically. This type of set up is not correct for most people because it is a statistical fact that most of us vary from the norm.

Having to use muscles to hold your head in the correct position for a good sight picture is not good. This causes stresses in the body, both physically and mentally, in order to get a good sight picture. It can quickly , even on the first shot cause trembling or shaking to a small degree but enough to cause a big miss down range.

Accurate shooting depends on no stresses in the body or mind that could cause movement, however tiny due to trembling or flinching.

Stresses also cause wobble and jerked shots. Setting up your scope properly takes a little work to do it yourself but the effort will be rewarded with a rifle that shoots more accurately easier. So how do we accomplish this. Read on.​

Mount the rifle in a stable position

You won’t be able to accomplish the set up properly if you are having to perform the tasks listed below and hold or balance the rifle unless you have 3 or 4 hands. Finding a good place to prop it on, like a table is not recommended either. The only way to properly secure the rifle for what comes next is with a properly designed rifle vise.

You can use any type of vise that is strong enough to hold the rifle securely while you do your work but make sure you have properly padded the jaws so not to cause damage to the rifle. Also it is easy to tighten larger machine vises much more than required for this job. If this happens you could easily destroy your rifle stock.

I have found it is always best in the long run to use the tool designed for the job. I have a gun vise that works perfectly. Of course if you only plan on installing one scope in your lifetime you may be able to get away with not buying one of these but as much as I shoot and play around with my rifles it has been a good investment for me.

If you want to look into purchasing a gun vise, I have been through several. I started with the cheap plastic ones and believe me, you don’t want to waste your money on these. Most will not hold the rifle stable without flexing and the plastic parts start to break after only a few uses. By the time you buy two of these you could have purchased one really good one.

I use a CTK Precision that can also be used as a shooting rest or sled. It is completely adjustable to handle all rifles in any position and comes with padded clamps that can be tightened sufficiently to hold the rifle securely. Below is the CTK and a few other good choices.

Install the bases and rings

With the rifle mounted solidly it is time to install the bases and rings. Make sure you have considered the ranges you will shoot this rifle. If you are truly planning for this rifle to be long range and you want to stretch it to it’s limit, you probably want to use a scope base that has additional moa built into it.

By using a base with an additional 20 moa built in, you are effectively adding 20 moa to your scope elevation adjustment capacity. This comes in handy when you are shooting at long ranges and your scope elevation adjustment has bottomed out ……but you need more. It is a wise idea to install these now. Once you are set up it is a real pain to pull everything back down again and be forced to start over.

Here are 20 moa bases to fit Anschutz, CZ, Marlin, Savage MKII , and Ruger 10/22 rifles. Install the bases using the torque recommended by the manufacturer. This is usually 25 – 30 in. lbs. You want to stick with the recommended number because if you go too tight and break one of the little set screws or strip out the threads, it is a real pain to get back out with no damage to the rifle. If you don’t tighten them enough you could fight accuracy issues until you figure out that your base screws have come loose.

Use a torque wrench designed for the job. Here is the one I have used for years. It comes in handy for a number of jobs in addition to being perfect for installing scope bases and rings. .

Also, be sure to use a little drop of blue lock tite on the threads of each screw before torquing them. Again, the last thing you want is for the base to come loose after all zeroing is done. Before you install the rings to the base, put the bottom half of both rings in place and tighten the mounting screws.

Then put your scope in place on top of the base. You are doing this to make sure your scope objective will clear the barrel. You do not want it touching but you do want it as low as possible without touching. The closer the center of the scope is to the center of the bore the more advantage you have on effective range when shooting later. See this article for more detail.

If your scope touches without seating properly in the rings, you will need higher rings or a higher cheek riser on the stock. If it is so high that you have to raise your head and can’t get a good cheek weld the fix might be lower rings. If it makes sense for you to do this because there is no other interference with the scope being lower, do it. You won’t regret it later.

Remember, one of our primary purposes here is to make the rifle fit you to eliminate stress, instead of vice versa. Click here to see several different height rings on Amazon. If you do purchase or order different rings make sure you order them to fit the diameter of your scope.

It will be either a 1 inch or a 30mm tube unless you are installing a very expensive scope which could be even larger. In any case the documentation that came with the scope will have this information. In some situations, like with ARs, there might be other equipment that prevents using lower scope rings.

If for whatever reason you have to run higher rings, you will need to install a good cheek riser. Accurate shooting at long range requires a good cheek weld.​​

Insure that the rifle is level in the vise

Now is a good time to ensure the rifle itself is level in the vise. Use a small level across the top of the base to ensure the rifle is level. You could install the bottom half of the rings and place the level across the top of them. Either method works.

There are kits available with one level that can be locked down on the barrel so you can always return the rifle to level if something happens and the rifle and vise are disturbed. Also, when locking down your scope, this level gives piece of mind that everything is correct. If you have one of these kits use one level as described above then lock down the barrel level. Now no matter what happens now you can quickly return the rifle to level using the barrel level as a reference.

You may also need a kit with lapping tools . Make sure the kit you purchase accommodates the diameter scope you are installing. Lapping is done after the bottom half of the scope rings are tightened to the bases. The tools are perfectly machined to ensure the ring openings are the right size and aligned with each other. It works like sandpaper on wood.

By moving the tool back and forth inside the rings, any material or high spots are removed to insure perfect alignment of the scope, while making sure the scope is not stressed at any point. Most rings don’t need it but it is always a good idea to use them if you do nothing but verify alignment.​

Adjust eye relief

Once you have your rings lapped and aligned correctly, install the bottom half of the rings with a little Lock tite on the threads, then put the scope into position and install the top half of the rings. Tighten the rings just tightly enough where you can still slide the scope forwards and backwards and turn the scope but there is a slight amount resistance.

Tighten all screws so that one side of the ring is not closer to the bottom half than the other side. They should be as even as possible. Do your best to keep them equal by tightening each screw in a tire lug type pattern.

With the scope in place and the rings tightened equally and just enough to still allow sliding and turning of the scope with a little resistance present, close your eyes and mount the rifle as if you were shooting from a bench. If you need to move the vice to get into a comfortable position, do so. It is important that you are in a position that will be repeatable in the field and stress free.

Once you have mounted the rifle as if you were about to take a shot, open your eyes and see what the sight picture looks like. Slide the scope forwards or backwards until you can see a perfect sight picture and your eye is aligned with the center of the scope when you open your eyes. ​

The eye relief built into the scope will determine how far away your eye is when the distance is correct. Realize that the picture might be out of focus. We are just looking to have the whole sight picture present when you open your eyes. No missing edges or black shadows around the edge. You may have to work at this for a few minutes to get it right.

When you think the scope is at the correct distance from your eye, walk away for a few minutes, then come back and check again. Continue to adjust the position until you are comfortable that the complete sight picture appears automatically when you mount the rifle.

Focus the reticle

Focusing the reticle has nothing to do with clarity of the sight picture down range. When doing this we are only trying to improve the clarity of the reticle itself.

With the rifle still mounted in a secure vice and stable, and with the eye relief correctly adjusted, the best method is to look through the scope pointed at a wall painted with in a light color. The reticle focus adjustment is located on the eye piece of the scope. Turn this knob until the reticle is clear and sharp, then lock it down with the locking ring. This is a very simple step that should only take a minute or so. Once you’re done, the reticle is set up for your eyes and you won’t need to this again unless your eyesight changes dramatically.​​​​

Level the scope to the horizon

Leveling the scope to the horizon is the most important step in setting up a rifle / scope combination to successfully shoot long range. Just a slight amount of cant in the scope can cause a huge miss down range. The longer the range, the bigger the miss.

There are a couple of techniques that I use to accomplish this task correctly. One can be done in your shop or anywhere you can put a mark on the wall without arousing the anger of your spouse. The other is best done at the range. Both techniques work well.

We will first cover how to do this inside assuming we can’t make a trip to the range soon. In front of the scope, while the rifle is still mounted in the vice, use a small carpenters level to draw a perfectly level line on the wall where your scope is pointing.

If you can’t draw a line on the wall, use any line that is known to be plumb with the ground, like the panels of a correctly hung door. Just make sure the rifle is also level when aligning the cross hair.

Now all that is left to do is align the vertical cross hair to the line drawn by using the level. When that is in line, your scope is leveled to the horizon.

Slowly tighten the ring screws, using the lug pattern. After each cycle of tightening, use the flashlight to ensure the scope did not turn. Continue this process until the ring screws are tightened to around 25 – 30 in. lbs or whatever the ring manufacture recommends.

If you are doing this job at the range, hang a brightly colored string with a heavy object tied to the end of the string from your target. A builders plumb bob works great along with a chalk colored snap line.

Check again to make sure the rifle is level, then align the vertical cross hair in the scope with the colored string hanging from your target. When it is perfectly aligned with the string, tighten the ring screws using the procedure discussed above. Your scope is now set up correctly for it’s best accuracy. ​​

Install a shooting level

Before you zero and while you have everything lined up and leveled, it is a great idea to install a shooting level. This is just a small bubble level that installs to your scope and allows you to check level right before you make every shot. Every serious shooter uses one of these to insure accuracy.

Here is the one I use on most of my rifles. It is made by Vortex. It’s made out of metal instead of plastic like most of the competing units and has done a great job of withstanding the rigors of hunting, traveling, and use at the range really well. Check it out on Amazon.

Proceed to the range to zero your rifle.


Yes this is a lot of work, but it is the only way to ensure the heart of your long range shooting system is set up correctly. Depending on a gun shop usually doesn’t work.

Believe me I’ve tried it. Each time I’ve tried to let a gun shop set me up, I have always had to take everything down and start over to get my scope set up correctly. Usually after the first zero trip to the range.

For a serious shooter this very frustrating. Once you have everything you need and understand what your are doing, this entire procedure will take less than 30 minutes. After you see the results from your shooting, it’s something you’ll be glad you did.