How to Mount a Rifle Scope on a Picatinny Rail

Scopes have become essential for every shooter. Although there was a time when they weren’t as popular, they’re currently irreplaceable. Using a scope will significantly reduce aiming errors and enhance your shooting experience. Nowadays, almost all rifles come with a drilled hole on their top part to enable the user to mount their own preferable optics.

Scope mounting on a Picatinny rail is a bit challenging, especially for new shooters. However, with time, it becomes a piece of cake. If you follow this guide, it won’t be long before you get the hang of it.

Understanding the Picatinny Rail 

There are several types of scope mounts, including Weaver, Leupold, Tip-off, Dovetail, and of course, Picatinny rail. We’ll focus on the latter for the time being as it’s the most commonly used shooting accessory you’ll encounter.

Picatinny Rail

Picatinny Rail

Being widely available, most rifles feature a pre-mounted scope on a Picatinny rail. This gives you two advantages; the first is that you won’t have to waste your time trying to figure out how to mount the scope on the rail manually. And the second is that the weapon will be lightweight, which makes other functions like hunting and aiming much simpler.

What makes such rails so different? Let’s go through the key features that make Picatinny rails stand out among the other types of mounts we mentioned earlier.

  • Slot Size: A Picatinny rail features a deep, wide slot compared to its counterparts.
  • Thickness: Because such rails are used as ejection port relievers, they’re usually thicker than 2-piece mounts.
  • Slots Spacing: The spacing of the spots on a Picatinny mount is pretty standard, and it extends along the entire length.

Why Use a Picatinny Rail? 

Using a Picatinny rail gives you several advantages. For starters, unlike other types of rails, this type minimized surface contact as it comes with a locking bar.

Also, you can forget about the canting shooters you usually suffer from while using bipod rails. Add to this the easy adjustability that’s counted for by the close spacing of recoils. This, in turn, enhances vision and grips while hunting or shooting at a range.

Last but not least, these rails don’t loosen up with frequent use. Accordingly, neither the rail nor the mounted scope needs to be retouched as time passes.

Mounting a Rifle Scope on a Picatinny Rail

Now that you’re aware of the advantages Picatinny rail offers you, it’s time to get to the more challenging part; how to manually mount a scope on it?

Tools You’ll Need: 

  • Screws: To fix the rings.
  • Torque Drivers: They’ll help you screw down the rings in place.
  • A Gun Cradle/Vise: You’ll need it to secure your rifle while you’re mounting the scope to avoid unnecessary slips.
  • Bubble Levels: For vertical and horizontal adjustments to keep the scope in line with the bore. 
  • Alcohol and Clothing: To clean your system if needed.

16 Simple Steps to Mount a Rifle Scope on a Picatinny Rail

  1. Unload your rifle by removing the bolt, then pull back the toggle to its standard position in order to lock the action open.
  2. Use a gun cradle or a gun vise to secure the rifle while you’re working on it.
  3. Start by separating the upper and the lower sides of rings because you’ll be fixing the lower ones first.
  4. To avoid mixing the sides up after mounting the scope, it’s better to mark the ends of both the upper and the lower sides using a piece of tape.
  5. Place the lower rings on the rail. They should be screwed loosely to the rail so as to stay in place while you’re fixing the scope. Yet, they shouldn’t be firmly tightened because you’ll need to make some adjustments to the alignment of your best rifle scope.
  6. Test the position of the scope by placing it over the rings. Make sure that your eyes are relieved before you fix the rings.
  7. You might need to move one of the rings backward or forward so as to properly adjust your optic. Don’t hesitate to make such changes; this is why you didn’t tighten the rings in the first place.
  8. Refer to the user’s manual to find out if there’s a specific gap length that should be left between the front and back rings. This widely varies between different models, which is why there’s no specific recommended length to provide you with.
  9. Once you’re comfortable with the position of the scope, keep it aside until you tighten your rings using a torque driver and the screws on both sides.
  10. Ensure that the rings perfectly fit in the rail, especially forward. It’s crucial to carry out this step because the scopes often thrust towards the rear whenever the rifle is recoiling.
  11. Start fixing the rings with great precision so as to avoid disrupting the alignment.
  12. Place your scope over the lower part of the ring one more time.
  13. Recheck that everything is in place. Try out the scope one more time, and feel free to adjust the power to its maximum limit.
  14. Go back a step for making adjustments if necessary. If not, then place the upper sides of things over the scope and keep them loose until you modify the scope level.
  15. Adjust the vertical crosshair so that it points towards the center of the bore while keeping the magnification power of your scope to the minimum.
  16. Finally, fix the upper sides using some screws and a torque driver to make sure the scope is firmly secured between both sides of the rings. 


As you may have noticed, it’s not hard to mount a rifle scope on a Picatinny rail. The trickiest part is positioning the scope; however, sooner or later, you’ll figure out what’s eye-relieving without the need to go through any guides.

That said, we’d like to point out that it’s essential to ensure that Picatinny rails are compatible with your rifle. Although they’re the most popular type of mounts on the market, they don’t work with some limited rifle models. Hopefully, you won’t be that unlucky.