Which Browning X-Bolt Scope Base Do I Need? (X-Bolt I vs. X-Bolt II)

Which Browning X-Bolt Scope Base Do I Need? (X-Bolt I vs. X-Bolt II)

Browning X-Bolt vs. X-Bolt II: The Definitive Guide

The release of the Browning X-Bolt II has brought some significant upgrades, but the biggest change for rifle builders and accessory shoppers is the simplification of the action geometry. Browning has effectively pared down the lineup from four action lengths to just two.

If you are looking to mount optics, this simplification is generally good news, but there are a few specific traps to avoid.

Visual ID: How to Spot the Difference

Before you measure anything, look at the receiver itself. Browning has made it easy to distinguish between the generations visually:

  • X-Bolt (Gen 1): The receiver is clean; there is NO logo stamped on the receiver itself.

  • X-Bolt II (Gen 2): You will see the "X-BOLT" logo clearly stamped on the receiver.

Short Actions: The Good News

If you are shooting a standard Short Action caliber (like .308 or 6.5 Creedmoor), compatibility is simple. All scope mounting holes are the same between X-Bolt 1 and X-Bolt 2 Short Actions.

If you have a rail for a Gen 1 Short Action, it will fit your Gen 2 Short Action.

Long & Magnum Actions: The Trap

This is where the consolidation from 4 actions to 2 affects fitment. In the Gen 1 era, Long Actions and Magnum Actions had different hole patterns. With the X-Bolt II, these have been combined.

CRITICAL FITMENT GUIDE: Gen 1 vs. Gen 2 X-Bolt

Gen 1 X-Bolt:
Different rails for Long Action vs. Magnum Action.

Gen 2 X-Bolt (X-Bolt II):
ALL Long and Magnum actions now use the Gen 1 Magnum hole pattern (3.93" spacing).

RIP Super Short Action (SSA)

The Super Short Action is dead. There is no SSA in the X-Bolt II lineup. If you have a Super Short Action rifle, it is strictly an X-Bolt 1. The new generation handles these smaller cartridges via the standard Short Action footprint.

Summary Cheat Sheet

Feature X-Bolt (Gen 1) X-Bolt II (Gen 2)
Visual ID No Logo on Receiver "X-BOLT" Logo on Receiver
Action Lengths 4 (SSA, Short, Long, Mag) 2 (Short, Long/Mag)
Short Action Spacing 2.94" (Same as Gen 2) 2.94" (Same as Gen 1)
Long/Magnum Spacing Split Pattern Combined (3.93")

If you are unsure, grab your calipers. 2.94" for Short Actions, 3.93" for Long/Magnum X-Bolt IIs.

Find all of our Browing X-Bolt Rails here!

Dec 17th 2025 Devin

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