Remove Rear Sight From 1975 Marlin Model 40

Removing the Rear Sight from a 1975 Marlin Model 40: A Comprehensive Guide

This guide provides a detailed, step-by-step process for removing the rear sight from a 1975 Marlin Model 40 lever-action rifle. This process requires careful attention to detail and the use of appropriate tools to avoid damaging your firearm. Safety should always be your top priority. Ensure the firearm is unloaded and the action is open before commencing any work. This article will cover various methods and potential issues you may encounter. Improper handling could result in damage to the firearm or personal injury.

Understanding Your Marlin Model 40 Rear Sight

The 1975 Marlin Model 40 typically features a simple, adjustable rear sight. It’s likely a ladder-style sight, meaning it has a series of notches or steps for windage and elevation adjustments. Understanding the sight’s construction is crucial before attempting removal. The sight is usually secured to the receiver via screws or a dovetail mount. Knowing which type of attachment you have will determine the tools and techniques needed for removal.

Tools You Will Need:

• Screwdrivers: You'll likely need both a small Phillips head screwdriver and a small flathead screwdriver. The specific size will depend on the screws holding your sight in place.
• Punch: A small brass or nylon punch is recommended to help avoid scratching the receiver. Steel punches can cause damage.
• Hammer: A small hammer, preferably with a soft face, will be necessary if using a punch.
• Sight pusher (Optional but recommended): While not always necessary, a sight pusher is a specialized tool that makes removing the rear sight much safer and easier, especially if it's a dovetail mount.
• Cleaning supplies: Gun oil, a clean rag, and a soft brush are helpful for cleaning up after the process.
• Safety Glasses: Always protect your eyes when working with tools.

Method 1: Screw-Mounted Rear Sight

If your rear sight is secured by screws, the process is relatively straightforward:

1. Safety Check: Ensure the rifle is unloaded and the action is open. Visually and physically inspect the chamber to confirm it’s empty.

2. Locate Screws: Carefully examine the rear sight for any visible screws. They're often located on the sides or underneath the sight.

3. Remove Screws: Use the appropriate screwdriver to carefully loosen and remove the screws. Avoid applying excessive force, as this could strip the screw heads or damage the sight.

4. Lift Off Sight: Once the screws are removed, gently lift the rear sight off the receiver. It should come off relatively easily. If it's stuck, try gently tapping the sight with the butt of the screwdriver, or use a punch as described below.

5. Clean and Inspect: Once removed, clean the sight and the receiver where the sight was mounted. Inspect for any damage or debris.

Method 2: Dovetail-Mounted Rear Sight

If your rear sight is mounted in a dovetail, it requires a more delicate approach:

1. Safety Check: Again, ensure the rifle is unloaded and the action is open. Double check the chamber.

2. Prepare for Removal: If you have a sight pusher, carefully clamp it to the rear sight. If not, you'll need to use a punch.

3. Using a Sight Pusher: If using a sight pusher, follow the manufacturer's instructions. Generally, you'll carefully position the pusher against the sight, ensuring it’s properly aligned, and then gently apply pressure to push the sight out of the dovetail.

4. Using a Punch (Less Recommended): Position the brass or nylon punch against the rear of the sight, squarely in the dovetail. Gently tap the punch with the hammer, using light and controlled strikes. Work your way around the sight gradually. Be extremely careful not to damage the receiver or mar the sight. This method is riskier and more prone to damage.

5. Remove the Sight: Once the sight starts to move, continue gently tapping until it's fully removed from the dovetail.

6. Clean and Inspect: After removal, clean the sight and the receiver. Inspect for any damage.

Troubleshooting Common Issues:

• Stuck Screws: If the screws are stuck, try applying a penetrating oil (like PB Blaster) to the screw heads and allowing it to soak for several minutes before attempting to remove them again. Avoid using excessive force, as you risk stripping the screws.

• Tight Dovetail: If the sight is extremely difficult to remove from the dovetail, consider seeking the assistance of a qualified gunsmith. Forcing it could permanently damage your rifle.

• Damaged Sight: If the sight is damaged during removal, it may need to be replaced. You can usually find replacement sights for the Marlin Model 40 online or at gun shops.

Re-installing the Rear Sight:

The re-installation process is the reverse of the removal process. Ensure the sight is properly aligned before securing it in place with screws or tapping it back into the dovetail. Again, if you are uncomfortable with this process, consult a qualified gunsmith.

Important Considerations:

• Gunsmith Assistance: If you're not comfortable performing this procedure yourself, it's always best to consult a qualified gunsmith. They have the experience and tools to safely and efficiently remove and re-install the rear sight.

• Safety First: Remember, firearm safety is paramount. Always handle your firearm responsibly and ensure it is unloaded before beginning any work.

• Proper Tools: Using the correct tools is crucial to avoid damaging your firearm. Avoid using inappropriate tools or excessive force.

• Documentation: Take photos or videos of the process before you begin. This can be extremely helpful during reassembly.

• Replacing the Sight: If your sight is damaged beyond repair, consider purchasing a replacement sight. Many online retailers and gun shops sell replacement parts for the Marlin Model 40.

This detailed guide should provide you with the knowledge and confidence to remove the rear sight from your 1975 Marlin Model 40. However, remember that working on firearms requires careful attention to detail and a commitment to safety. If you have any doubts or concerns, seek the advice of a professional gunsmith. This ensures the safety of yourself and the preservation of your firearm. Always prioritize safety and responsible gun ownership. This information is for educational purposes only and should not be considered professional gunsmithing advice.