How to Properly Mount a Rifle Scope

Mounting a rifle scope may seem like a daunting task, however it’s not as complicated as it may appear. As long as you take a few things into consideration, you should have a pretty easy time installing your new scope on your rifle.

The first thing you want to consider is what rings and bases you will need. There are a couple different ways to mount a scope to a rifle. Method one uses rings that attach directly to the receiver of your rifle. The other method uses two separate components, a picatinny base that will attach directly to the receiver of your rifle and either a single piece mount or a set of scope rings that attach directly to the picatinny rail. 

Here are some things to consider regarding which bases to use:

1. Do you need a picatinny rail?

Not necessarily, a pic rail is helpful if you’re looking for an easy way to quickly detach your scope and move it from one rifle to the next. However, I wouldn’t bother with one if you’re planning on leaving that scope paired with just one rifle.

1. You also might consider a pic rail if you’ve used a decent amount of adjustment to get to zero. In this case, I would advise the use of a 20 MOA rail. This will raise the back end of the scope higher and allow for less adjustment to be used to get to zero.

Now that you’ve decided on the bases that you’re going to use, you need to figure out which rings will best fit your new scope. 

First of all, you will need to buy rings that correspond with the tube diameter of your scope. If you have a 1” tube, buy 1” rings, 30mm tube, buy 30mm rings.  

Now, the height of the rings can be a bit subjective. Generally speaking, you want to mount the scope as low as you can without making contact with the barrel of your rifle. In most cases, you will want to go with low rings if you have a scope with an objective size of 50mm or smaller, medium rings for 50mm and larger, and high rings for 56mm and larger.

The ring size you choose can vary depending on the shape of your scope and the contour of your barrel. For instance, when mounting my personal scope, I could have gotten away with low rings as I mounted my scope on a 20 MOA picatinny rail, however, the medium rings provided a better fit without being too high for my cheek weld.

When choosing the height of your scope rings, you will need to consider where your cheek comes to rest on the stock of your rifle. You want to make sure that you are not mounting your scope above or below your eyeline as you want to be able to see clearly through the scope as soon as you raise your rifle to your shoulder.

Another point to consider when choosing rings is the caliber of your rifle and your recoil. You want to ensure that your rings are going to support your new scope through the recoil of your shot. Obviously, a .338 Lapua will have a more substantial recoil than a 6.5 Creedmore so you might want to pair heavier rings with heavier calibers.

Once you have your rings and bases squared away, it’s time to actually install your rifle scope. The best thing you can do is make sure that you work on a level surface. It also helps to have a gun vice or a saddle of some kind to hold your rifle. 

The first step is to remove the screws or plugs in the receiver and install your bases. Whether I am using a pic rail or not, I personally like to use a small dab of blue loctite on the screws that attach the base to the receiver. I like to torque my bases down to 35 inch pounds.

Once you get your bases on, install the bottom half of your rings, (top portion removed). If installing on a pic rail, make sure you follow the torque specs of the rings you’re using. Most of the time, the connection of the ring to the rail will require about 45-65 inch pounds of torque.

Now that the bottom half of your rings are installed, it’s time to set your scope in and level the reticle. This is where it helps to have a little bit of OCD. What I like to do is get the scope as level as possible, and center the turrets over the bolt, then install and lightly tighten the top portion of my rings. This will help keep the scope in place but also allow for some rotation so you can make sure your reticle is level. 

I like to compare the vertical axis of the reticle to the back end of the bolt and make sure that that vertical line isn’t crooked. It also helps to use a small bubble level on the top of the elevation turret of your scope. Another thing to consider here is your eye relief, shoulder the rifle and make sure that you can see clearly through your scope without having to adjust your face forward or back.

Now, you finally have your scope and reticle level, and it’s time to tighten everything down. I tend to get a little meticulous here as it’s easy to move your scope during this process so I constantly check back and make sure my reticle is still level. 

Using a torque wrench, try to tighten your rings in an alternating pattern to make sure each side is tightening evenly. I prefer to do a quarter turn on each screw then check my reticle and continue until I feel resistance in the screws. It’s at this point that I slow down even further and make sure that everything is going down evenly. 

It’s very important to follow the torque specs of the rifle scope but in general most rings should not be tightened past 17-20 inch pounds. Once everything is tight, double check your work and you should be all set.

As you can see, properly mounting a rifle scope is not terribly difficult. It just takes a little time to make sure you’ve done it right. The most important thing is to make sure that you have properly tightened everything down. Make sure to refer to the torque specs provided by the manufacturer of your scope, rings, rifle, and bases and tighten everything accordingly. 

Additionally, make sure that you set your eye relief for your eyes and level your reticle. Even a small amount of cant can make a big difference out to distance.