The Perfect Set Screw Size For Your Ruger American Rear Sight

The set screw on the rear sight of a firearm, such as the Ruger American Rimfire, serves the important purpose of securing the rear sight in place, allowing for adjustments and removal. To remove or adjust the rear sight, it is essential to first loosen this set screw. While a standard screwdriver can be used for this task, selecting one that fits the set screw properly is crucial to avoid any damage. In the case of the Ruger Mark IV (2019), the rear sight set screw hex wrench size is .05, which is equivalent to 1.3mm. This information can be particularly useful when dealing with small screw slots that require specific tools for adjustments.

Hex wrench size for Ruger Mark IV rear sight set screws

The hex wrench size for the set screws of the rear sight of a Ruger Mark IV is .050" or .05". This information comes from a Ruger Forum discussion, where a user confirmed the hex wrench size with Ruger Customer Service.

The rear sight of the Ruger Mark IV has two set screws that fit into the dovetail. One user in the discussion mentioned that the hex wrench size is so small that it felt like it would strip out. This user swapped out the screws for slotted screws to avoid having to carry a tiny hex wrench to the range.

Another user in the discussion recommended cleaning the screws and holes with acetone and using blue Loctite to secure the screws in place. This user reported that after 200 rounds, the screws had not moved.

It is important to note that the rear sight set screws on the Ruger Mark IV may vary in size depending on the specific model and year of manufacture. Therefore, it is always a good idea to refer to the owner's manual or contact Ruger Customer Service for the most accurate and up-to-date information regarding the hex wrench size for the rear sight set screws.

In contrast, the Ruger American Rimfire rear sight set screw does not require a hex wrench. According to a user guide, a standard screwdriver is all that is needed to loosen and remove the set screw. It is best to use a screwdriver that fits the set screw properly to avoid damaging it.

Removing the rear sight on a Ruger American Rimfire

The rear sight on a Ruger American Rimfire can be removed by following a few simple steps. Firstly, it is important to note that you will need a screwdriver to loosen the set screw located on top of the sight. It is best to use a screwdriver that fits the set screw properly to avoid damaging it, and a standard screwdriver should suffice.

Once you have the correct screwdriver, simply loosen the set screw. At this point, you can adjust the windage and elevation as needed. If you are only interested in removing the rear sight, continue to the next step.

After the set screw has been removed, the rear sight can be gently slid off the dovetail. It is important to handle the rear sight with care to avoid bending or breaking it during removal. Additionally, ensure that you apply gentle pressure while sliding the rear sight off to avoid damaging the sight or the firearm.

If you wish to reinstall the rear sight, simply slide it back onto the dovetail and tighten the set screw. The rear sight should be aligned with the front sight and the target when aiming.

It is worth noting that the rear sight on a Ruger American Rimfire can be replaced with a different style by following the same steps for removal. There are aftermarket rear sights available that offer different styles and features.

Additionally, if you are having issues with the alignment of your rear sight, you can make adjustments by tapping the base of the sight with a rod and "drifting" it in the direction you want it to go. This can be done by placing the rifle on a towel and holding it firmly by hand. It is recommended to use a brass rod or punch for this process, as brass is hard enough to make adjustments but won't cause much damage if you slip.

By following these steps, you can safely and effectively remove, adjust, and reinstall the rear sight on your Ruger American Rimfire.

Adjusting the rear sight on a Ruger American Rimfire

Step 1: Loosen the Set Screw

Use a screwdriver that properly fits the set screw to avoid damaging it. Loosen the set screw located on top of the rear sight. This will allow you to adjust the sight and make the necessary windage and elevation changes.

Step 2: Adjust Windage and Elevation

To adjust the windage, you can use your fingers, and if it's a little stiff, a penny inserted into the slot of the windage screw will help. For the elevation dial, use a pointed object, such as the tip of a golf tee, to make the necessary adjustments. Make sure to adjust in the correct direction, as per the instructions in your manual. Remember that you move the rear sight in the same direction you want the round to go.

Step 3: Secure the Rear Sight

Once you have made the desired adjustments, tighten the set screw securely to hold the rear sight in place. Ensure that the rear sight is properly aligned with the front sight and the target when aiming.

Upgrading the Rear Sight

If you're looking for a more permanent solution or prefer a different style of rear sight, you can upgrade to aftermarket sights designed for the Ruger American Rimfire. Options include aperture sights, such as the Tech Sights MXT200, or the Williams peep sight. These sights typically offer easier adjustments and provide a clearer sight picture.

When upgrading or making adjustments, always handle the rear sight with care to avoid bending or breaking it. Additionally, regular maintenance and checking of the rear sight's security are essential to ensure it doesn't come loose during use.

Ruger LC9 rear sight lock screw

The rear sight lock screw for the Ruger LC9 pistol appears to be available as a standalone purchase from Ruger. This is part number CP08001, described as a "Genuine Ruger Factory Accessory".

The rear sight screw requires a 2mm Allen (hex) wrench to remove it. It is important to note that the rear sight holds the firing pin block in place, so it should not be removed until you are familiar with how it is assembled. The rear sight should only be loosened by a quarter turn before being slid out from left to right. This is to prevent the spring plunger from being caught by the screw.

When reinstalling the rear sight, the spring plunger must be tucked back under the sight. This can be done by slowly working it under and holding it in place with a small piece of paper until it is far enough over.

Ruger rear sight base screw for Mark 1, 2, 3, I, II, III, MKI, MKII, MKIII, and 22/45

The Ruger rear sight base screw is a factory rear sight set screw that fits modern rear sights, not the old "Micro" sight. It is used to tighten the sight base to the receiver dovetail groove. This screw is compatible with the following Ruger models: Mark I, II, III, MKI, MKII, MKIII, and 22/45.

The set screw for the Ruger Mark IV (2019) rear sight is a hex screw that requires a hex wrench. The exact size of the hex wrench required has been a topic of discussion among firearm enthusiasts, with some suggesting smaller sizes such as 1/16" (SAE), 1.5mm or 1.3mm (metric), or 0.05" (SAE). Ultimately, it was confirmed by Ruger Customer Service that the correct size hex wrench for the Mark IV set screw is 0.05".

For the Ruger Mark-Series, there is also a set of four grip screws available, which are compatible with the MKIV 22/45 Lite, MKIII 22/45 Lite, and SR1911 Commander models.

In addition, there is a Ruger scope base that is compatible with the MKI, MKII, and MKIII models. This scope base has received positive reviews for its fit, quality, functionality, appearance, and ease of installation. It is made of clear anodized aluminum and measures 8.0" in length, 3.5" in width, and 2.0" in height.

Frequently asked questions