Ruger No. 1 Picatinny Rail & Scope Base Fitment Guide

Measure the mounting-hole pattern, recoil-pin locations and barrel contour before selecting a Ruger No. 1 rail.

1. Verify the rifle before selecting a rail

Ruger No. 1 rifles were produced with different barrel contours, mounting-hole patterns and recoil-pin locations. Rifles that appear similar may require different rails.

Check all of the following:

• The spacing between the mounting holes
• The center-to-center spread between the mounting-hole groups
• The locations of the barrel recoil pins
• The barrel contour at the front and rear mounting locations

Do not select a rail using only the rifle’s caliber, year, barrel length or model description.

2. Available Ruger No. 1 rails

Both rails are HD 0 MOA rails machined from 7075 aluminum.

3. Use the printable fitment guide

EGW provides a printable guide for checking the barrel contour and mounting-hole pattern. Print the guide at 100 percent or “Actual Size,” then confirm that its one-inch reference line measures exactly one inch.

Ruger No. 1 Radius Gauge and Hole Spacing Guide 

The barrel contour and all mounting measurements must match. A single matching measurement does not confirm fitment.

4. Recoil-pin locations

Ruger used different recoil-pin locations on some No. 1 rifles. The recoil pins should be compared with the recesses shown on the product page or printable guide.

On the B/S contour rail, every recoil pin does not necessarily need to enter a machined recess. The mount can function using the rear recoil lug and mounting screws when the barrel contour and mounting-hole pattern are otherwise correct.

5. Important exclusions

• These rails are not compatible with the Ruger No. 3.
• Do not order solely by caliber or barrel length.
• Do not modify or enlarge the mounting holes to correct a mismatch.
• If the measurements do not clearly match either rail, contact EGW Support.

6. Installation information

Use a small drop of blue threadlocker during installation.